22 Families Took in 77 Kids. Decades Later, Texas Couple Behind Movement Open Up About 'Amazing' Adoptions

More than two decades ago, 22 families from a small part of East Texas joined together to adopt 77 foster children in need.

Now, their story is hitting the silver screen as they continue to push for people to support kids in the system.

Sound of Hope: Story of Possum Trot, which opened in theaters on Thursday, tells the story of how Bishop W.C. Martin and his wife, Donna Martin, led the charge within their Bennett Chapel church in Possum Trot to adopt “the most difficult-to-place children” in foster care in the 1990s.

As W.C. explained to PEOPLE at the time: “I never dreamed there were so many children in the system. We’re just a little church. But this problem is all of ours.”

Both the bishop, 77, and church's first lady, 68, are still encouraging others to make a positive impact on a foster child’s life by giving them a stable home. Speaking with PEOPLE in a new interview, they say they are also still concerned about the number of kids in the system that are seeking homes.

“The system is swelling up every day, and it's time for a change,” W.C. says.

It has been more than 20 years since the Martins adopted their first kids. They went on to adopt four in total, adding to the two biological children they had.

Now, all six of the Martins' kids are full-grown adults: Princeton is 44, LaDonna is 38, Terry is 35, Josh is 34, Mercedes is 33 and Tyler is 30.

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The bishop and first lady are grandparents now, too. Tyler just welcomed son Tyler Jr., nicknamed J.R., while Josh is expecting a child with his fiancée, who is due in November. And LaDonna will give birth in December.

Donna says it has been “amazing” to watch the kids she adopted grow over the years. “I've learned so much from the children,” she says. “They have taught us what life is."

And while there were certainly challenges and adjustments along the way, “I don’t know where I’d be [without them], probably the street," son Josh told PEOPLE back in 2012. "My parents are nice, loving and kind.”

The Martins' work has had a ripple effect, they say, especially among church leaders and members. 

The bishop tells PEOPLE he has received “multiple” phone calls over the years from those who have been inspired by his family’s story: “They are realizing how beautiful it is for them to step into somebody else's life and to help them to grow up and be what they need to be according to the will of God.”

Now, the adoptions encouraged by the Martins' church are the center of Sound of Hope: Story of Possum Trot, starring Demetrius Grosse (Straight Out of Compton, Rampage) as the bishop and Nika King (Euphoria) as the first lady.

After about 10 years of setbacks, the film, executive produced by Black Panther’s Letitia Wright, opened this week.

W.C. and Donna say its title, Sound of Hope, has special meaning to them.

For the bishop, it means that there's "hope for the children, hope that they will find a primacy in their life, a home, a mother, a father, love and God.” For the first lady, it reminds her of the Bible's Hebrew 11:1, which promises that “faith is the substance of things to hope for and the evidence of things not seen.”

“So with the faith in God, we are hoping and trusting that we can annihilate this problem,” she adds.

Ultimately, W.C. says he and his wife pray that every child in the foster care system “will find a beautiful home, loving parents and a place where they could feel safe and know that this is the Lord's doing, and is marvelous in our heart.” 

“It should not be a child waiting on a home," the bishop says. "It ought to be a home waiting on a child."