Jessica Biel Celebrates Son Silas' 5th Birthday: 'We're at Home, Covered in Legos and Birthday Cake'

Happy birthday, Silas Randall!

Jessica Biel wished her son Silas a happy fifth birthday on Wednesday with a throwback photo from last summer, sharing that today, the family is “at home, covered in legos and birthday cake.”

“This little man is 5 today!” wrote Biel — who celebrated her own birthday last month with a pajama party — in a caption accompanying a photo on Instagram of Silas being carried over her shoulder.

“We’re at home, covered in legos and birthday cake right now… but I just found this pic on my phone from last summer and it made me so happy,” Biel, 38, continued.

The actress said that in honor of Silas’ milestone birthday, she and husband Justin Timberlake are “supporting @savethechildren and @feedingamerica, who are doing so much good work to keep kids and families healthy and fed during this time ❤️.”

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She also encouraged her followers to “scroll through your old pictures today and post something that brings you a little bit of joy! Sending lots of love to you all…”

Timberlake, 39, shared Biel’s post on his Instagram Stories, adding, “Our dude is 5!!” with a mind-explosion emoji.

Biel shared with Ellen DeGeneres last year that Silas enjoys Legos and swimming — and has become quite the jokester.

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“Now he is telling the joke and gets the joke,” Biel said on the talk show in October of her then-4-year-old, joking, “Which is terrifying.”

Timberlake has previously said that he’d love to have more kids with Biel.

“I want to have as many kids as we can, if I’m being honest,” he said in 2018 while speaking with Zane Lowe for Beats 1.

He added later in the conversation, “I feel like the success of parenthood is feeling like I failed all day today, but I get to wake up tomorrow and do it again … and hopefully they turn out to be a good human being.”