This Is Us producer breaks down Kate and Toby's downward spiral and Jack Jr.'s trauma

Warning: This story contains spoilers from Tuesday's episode of This Is Us, "Saturday in the Park."

Here's the good news: The Big Green Egg did not catch on fire, burn the house down, and snuff out another beloved Pearson patriarch. The bad news: The 10th anniversary party for Rebecca (Mandy Moore) and Miguel (Jon Huertas) was not spent celebrating the love of one of the key couples on This Is Us — it was all about a different one continuing to go up in smoke.

After weeks of tension, visions of good 'ol versions of partners, reluctant ultimatums, and secret job prospects, Kate (Chrissy Metz) and Toby (Chris Sullivan) found a new way to reach a new low in their marriage, which is hurtling toward its disquieting destiny of divorce. Titled "Saturday in the Park," the episode — specifically its present-day story — radiated bad vibes from the get-go: In the opening scene, viewers saw sight-impaired Jack Jr. (Johnny Kincaid) trying to block out his parents' constant fighting, and, as it turned out, he was obsessed with going to the park because that was the place where Mommy and Daddy were actually happy.

Things soon turned from bad to nurse: When Toby forgot to latch the gate in Jack Jr.'s room (despite being repeatedly asked to remember) — and Kate forgot to lock the front door — Jack Jr. wandered outside and escorted himself to the park. Fortunately avoiding the cars whizzing by as he crossed the street, Jack Jr. made it to the park, where he face-planted on the cement and cut open his forehead. (While Kate and Toby searched in vain for him around the house, memory-challenged Rebecca was the one who pieced together his whereabouts, based on his footwear.)

After Jack Jr. received his stitches, Kate re-opened the wounds of her relationship, and she had it out with Toby on the front lawn. As things turned increasingly ugly and honest, Randall (Sterling K. Brown) and Kevin (Justin Hartley) arrived at the house, rushing to her defense. (It was a show of Big Three unity that was echoed in the episode's flashback story, which featured the trio banding together against the unpleasant babysitter, hired by Milo Ventimiglia's Jack and Rebecca so they could try to enjoy their first night out alone in six years.) "Perfect," sneered Toby as Kate was absorbed back into her sibling unit. "The way it's always been." The episode ended with Kate lamenting the state of her crumbling marriage to her brothers: "I don't know if Toby and I are going to make it." (The same could said for the fast-failing plumbing in the house, which Toby had tried to fix last year before calling his dad. While you decide on the best metaphor for a marriage that's taking on water, also remember that fatherly wisdom that Toby was once offered: "People only look for leaks when the water's coming out, but it's the pressure that'll get you.")

And now, we rhyme with turd with curb, avoid sandboxes full of tetanus, spell anniversary correctly, marvel drunkenly at some lumpy potatoes, and change our emergency contact info as we stroll through the "Park" with exec producer K.J. Steinberg, who wrote the episode.

ENTERTAINMENT WEEKLY: Welp, the situation worsened yet again. We know what lies ahead in the future for Kate and Toby. How close are we to the point that Katoby is kaput?

K.J. STEINBERG: I think at the end of the episode, there's still hope. There's a recognition that something's gotta change. They are at the rubicon. If they don't pay attention to this marriage — if they don't give it their full focus — it's doomed. We need to go into [the next] episode knowing that Kate and Toby are good people, who have so much love for one another, but that love has gotten lost in the distance and the way that they have evolved individually without converging in that evolution. Their lives have strangely taken different paths. The end of this episode gives them clarity that they really have to stop just hoping things get better. They need to work to make things get better.

Given their stack of issues and lack of connection points, how do they put in that work? Where might they turn for help, professionally and personally, especially given the challenges in their family?

They're going to do whatever it takes, but they won't know what that is until they're in it. And it's not going to look like what they thought it would look like. And it's not going to look like what the audience thinks it's going to look like.

What intrigued the writers about setting this chapter of the downward spiral around Jack Jr. — and how did you all settle on the idea that viewers would see some of it through his perspective, literally?

Children, whether they're sighted or unsighted, they hear and they feel everything that's going on with their parents, in a household, in a marriage. Even the very little ones, they see truth. The adults are often lying to themselves and each other about how things are going in the family. They're letting things slide. They are just trying to get through the everyday. But the children see and feel every vibration — and especially Jack, who spends his life hearing and feeling his way through the world. He's hearing and feeling his way through his parents' conflict in a way that no other character on the show could experience or express.

We've watched marriages dissolve on television a million times and we thought, "What is our way of doing this?" And in a show that toggles between past and present, between the child versions of our characters and the future versions of our character, it seemed very fitting and organic to tell the story of the dissolution of Kate and Toby's marriage through the point of view of this very, very special young boy.

Little Johnny [who has low vision and nystagmus] was impressive in this episode. What sticks out to you about filming these scenes with him?

He is pure joy. He infuses the entire cast and crew with joy, and he is in the moment. He teaches and reteaches how to be present. When he was crossing that street alone, we owned the street. We all made sure that he was safe, but it was so striking and arresting — the image of this little unsighted child with his innocence and his beautiful face. Walking the world alone, he looked so small. Every take where the stunt car would pass by, everyone on the crew was holding their breath, and every time "Cut!" was called, we all let it out. We all felt like we were responsible for him, and he represented something to us.

Also, one adorable thing that he would do every time is he would call the bell. Before we start a take and we roll, we need to lock the set down. So the red lights go on, everybody quiets down so we could start filming. So he would — with his little voice — call to our 250-person company, "Belllll!" And sometimes he would say, "Cut!"

Sounds like he'll be directing, like the other cast members, by the end of the season! How much of a wake-up call for Kate and Toby was it to see that their tension in the house led to near tragedy with their son, who revealed that he wanted to go to the park because that's the place where Mommy and Daddy weren't fighting?

It was an earthquake of a wake-up call for them. Children externalize what we think we're hiding as parents. And often in families, it takes the child to speak through a megaphone, in whatever way that is, to wake and shake the family up. Were it not for this near tragedy, Kate and Toby could have gone on forever in a mire of unhappiness without making a change.

Toby and Kate have become increasingly blunt and harsh in their fights. There are some hurtful and honest things said in this episode, such as Toby saying to Kate, "Did you even want me to move back to L.A.?" and telling her that it's irresponsible that she doesn't see Jack Jr.'s limitations, or Kate saying that Toby was pulling away before the San Francisco move and that she was the only parent in this family. As you were writing these words, whose truths and barbs hit the hardest?

The things that hurt the most between this couple are the hurts that they've been harboring the longest. In a marriage, you're fighting about the thing that's in front of you, but then when you get to those raw fights, it's the stuff that has been sitting vulnerably and deeply for so long that are the most hurtful. It's such an interesting question, because one can say that it's most hurtful to Toby that Kate is accusing him of having separated from them in his heart when he realized Jack's challenges. But one could also argue that that's Kate's deepest hurt. Even though she's launching those words at Toby, that is the most painful thing for her to have to say and have to live with.

The same thing on the flip side: When Toby says, "Do you even want me here?," he's basically saying, "Do you love me anymore?" Through all the noise of the trauma of what they've been through in that episode, on that day, it's probably what he's wanted to ask her for the past year: "Do you love me anymore? Do you want me in your life anymore?" That is the most hurtful in the same way in that it's the most wounded part of him that's saying it and the most vulnerable part of him that's saying it. But in that moment, it's the most wounding thing to say to her.

Both Kate and Toby have the best intentions, and they are coming into their own. They also legitimate grievances. How many of the issues in their marriage are rooted in the fact that these two have always been adding more responsibility than they might be able to handle? That's challenging enough for a relationship, but on top of that, they fail to communicate in healthy ways, which is deadly.

It's a cautionary tale, for any relationship. They met and they were both damaged, and ready to heal. Kate certainly was ready to heal. If you were really to postmortem this relationship, Kate was at a place where she was saying, "Enough is enough on the way that I've been living and the way that I've been hurting myself and the way that I haven't been loving myself." And she said, "Dammit, this is the moment I step into this weight-group meeting, and I start to heal, I start to really love myself and I start to get healthy." That is the moment where she met this joyful guy who, in a charming way, wouldn't take no for an answer. One could say that the distraction of that was wonderful for her because she fell in love with someone who loved her for everything about her — but maybe missed a crucial part, which was: Did he fall in love with her struggle to get healthy, or with her goal to get healthy in all of the ways that she wanted to get healthy?

I think that he helped. The love that he gave her was healing and is healthy. And she did get healthy in so, so many ways in that relationship. But her journey to self-fulfillment and to self-actualization eventually moved beyond that honeymoon phase. As he says in episode 9, "You fell in love with a coping mechanism." To your point, there was a certain part of both of them that lost that focus, and kept heaping on responsibilities. Both of them had waited so long for their real lives to begin. As often happens with couples who get together later in life, they suddenly realize that the clock is ticking on their dreams, for their way their lives are supposed to look. You've always wanted kids? You do that right away. And so they kept going and going, and heaping on more familial and parental responsibilities, and maybe ignoring what was happening right in front of them, between them. Which is a really normal, natural thing that happens in the exhaustion of parenting.

Toby's forgetting to latch the gate, after repeated reminders, presses all the wrong buttons for Kate. And yet she accidentally left the front door unlocked, which is brought up in their fight. She's ding-ing him when she did something somewhat similar, too, but to her, his lapse is a referendum on the way he parents and how present he's been.

I think it's a huge symbol for her. The metaphor of keeping him safe or letting him roam and be independent, when to close that gate and when to open it — she's the arbiter of those decisions and he is not around enough to know. The gate has become a point of conflict for them. It's become a symbol of how well he does or doesn't parent, how well he does or doesn't know his son. Because she's put so much on the importance of the gate, I wonder if somehow, subconsciously — not that Toby would ever want Jack to be unsafe — but if there's some underlying resentment and rebellion in not wanting to parent the way that she asks him to, in him wanting to parent the way that he wants to.

Toby has always felt like an outsider to the Pearsons on some level, and he wanted to be Kate's No. 1, not Kevin. At the end of the episode, he sees her brothers step in to defend her, and she's standing with them, and he's like, "Perfect. The way it always is." How much of his insecurity about his value in her life is in play here?

Any person that marries into a really close family — especially one bound by tragedy — it's hard to penetrate. Even not bound by tragedy. Any close family with close siblings. Especially with this very specific landscape of the Pearson family with triplets. I mean, the Big Three literally grew up going through every phase of life together at the same time. So there are bonds there that are impenetrable. I have always felt for Toby in trying to compete with those. There's not only bonds, but a layer of the protective brothers. There's also that genetic bond of the twins that Kate and Kevin have, where when they were babies, they would only stop crying and be able to comfort themselves to sleep if they were in the crib together. And that never went away.

Maybe Kate is saying that through parenthood and in the marriage was the opportunity to break through and become her No. 1. And there were missed opportunities for both of them. I don't know if you ever can break the bonds of siblinghood, the way that the Pearsons had it. I think you need to create your own space and your own place that is at once accepting of those sibling bonds, but also appreciating your own space. He shared children with her and a bed with her, and that's a space that obviously her brothers don't. So I wish that that had been enough for him — and I wish that Kate had made that feel to Toby like it was enough.

Take us inside the writers' room. Did most people see both sides of this marital crisis and feel conflicted, and/or were there times when half the room was on Team Kate and half was on Team Toby, which led to some passionate debates?

No writer was ever on one side consistently. The way that we got balanced points of view is we had passionate debates about every moment between them: "If Toby says this, what is a fair and true thing for Kate to come back with? And let's not be afraid to have Kate not come out looking great in this scene, because we know when we tell a balanced story about a marriage that feels real to us, Toby's probably going to make a mistake in the next scene."

Like any clear lens on a marriage, you're going to be taking one person's side over the other person in any given moment. And what we endeavored to do — it's like a good documentary. You leave one scene with one really strong opinion, and you think you know how you feel about the subject. But then in the next scene you get a different angle, and you're like, "Oh man, wow, I was wrong. I really see it this other way." I think what we endeavor to do is put [a] documentarian's lens on a marriage, where your feelings and your perspective shifts with every new angle and with new piece of information. The deeper you go, the clearer you see, and then hopefully at the end, you're going, "God damn, I don't know who's right and who's wrong."

Did you personally view Kate's act of putting her name in for the job in L.A. as empowering and necessary for her self-actualization, or as counterproductive to their troubleshooting and a bit selfish, as Toby says? Or were you somewhere in the middle, torn?

I felt it was an act of triumph for the character as a whole. In my own marriage, when I'm acting like a warrior for my own cause, sometimes it's coupled with a degree of immaturity. "Well, if he did this this way, then I'm gonna do this this way." So I thought it was mostly triumphant. But there was a part of me that thought, "You just got mad at Toby for making this move without transparency." But she was doing in that moment what she thought she had to do — perhaps to not be dissuaded from doing it. Often when you are in these intimate relationships, you feel like if you listen to anybody's voice other than your own, you might not have the strength to do it. And in the final analysis, I feel that she didn't tell Toby she was going to do it, because maybe she was afraid that she'd get talked out of doing what was best for herself.

Viewers didn't get the Miguel-Rebecca backstory they've been waiting for. The episode with their anniversary party would've been a logical place to flashback to it. Then again, they didn't even get their anniversary party. How soon is the Miguel-Rebecca reconnection story coming?

You're going to get an epic, satisfying, gorgeous version of it in episode 15.

By the way, did Mandy really whisper anything to Milo about what Rebecca was going to give Jack at their next anniversary? And if so, was it the secret ingredient to the sugar pie?

I don't know the secret ingredient to the sugar pie [laughs], and I'm pissed about that. And yes, Rebecca did whisper something — and like at the end of Lost in Translation, I will never tell.

So you had an idea and you told Mandy what it was?

No, Mandy came up with it herself.

Viewers saw two sides of Rebecca and her state of health: She is the one in the family who's sharp enough to figure out where Jack Jr. has gone, but at the hospital, she whispers to Kevin tp help her fill out the forms. Now that she's said to her children what she needed to, is the show saying to viewers, "Brace yourselves. We're getting to some real painful moments of decline"?

I would say: Brace. This episode is a really good snapshot of this moment in time in her disease. I have a family member who's going through it and I visited her yesterday. And what was so interesting — and it really echoes Rebecca's journey — is that in the same 40-minute visit I had, she didn't remember who my husband was, but then remembered the story of how he and I met. Both things can be true. For loved ones going through this phase of this cruel disease, in one moment the memories are slipping through their proverbial fingers, and the next moment there's crystal clarity. For loved ones watching it, and for the audience watching it, this snapshot of Rebecca in this episode is appropriately sort of confusing, in how utterly capable she is of putting together the clues and then in the next moment she can't even remember Jack Jr.'s birthday.

Kevin had second thoughts about his second thoughts on Madison (Caitlin Thompson), especially when he found out that Elijah (Adam Korson) is going to propose. Randall wisely talks him out of it. Can we consider the Madison door closed now — or might we have another situation on another wedding day?

I think it's beautifully closed. But whenever there's love between people — real love, which they do have, and the inextricable bond of sharing children — there's always a possibility. For these characters in this moment, it's actually this deeply bittersweet definition of what love can look like, in a different form.

I mean, she did "Hey, Kev?" him three times when he started to leave. And they had some lingering looks. How do you recalibrate or redefine that love?

They do not want to let each other go. That's the answer. But sometimes, you have to — in certain ways.

There's a lot on the line for Toby and Kate in the next episode. What's your cryptic tease?

Structurally it's really different — and really interesting. It moves through time in a way that gives you a scope that will really help you understand. And it earns. It really earns what we've all been afraid of: "Will the show be able to earn this iconic couple splitting up? Will the audience ever be able to understand and accept both sides and love them both at the end of it?" And the answer is, "Yes."

This interview has been edited and condensed for length and clarity.

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