Timberlake and Biel welcomed their first son, Silas Randall, into the world on 11 April, 2015. According to People, Silas was named after Timberlake's grandfather and great-grandfather. Silas also has the same middle name as his singer dad, as per ABC 7.
Back in 2021, Timberlake opened up about how Silas felt about becoming a big brother during an appearance on "The Ellen DeGeneres Show" (via People) saying, "Silas is super excited." "Right now he's very much liking [having a brother]," he added at the time. "But, you know, Phin can't walk yet or chase him down, so, I don't know, we'll see what happens."
Of Silas's interests at the time, Timberlake shared, "He is [musical], but he's into Legos and tennis and . . . we got him a Nintendo Switch . . . I don't know if you've ever seen a child when you threaten to take their technology away, but it's like, 'Come on, Daddy, don't do me that way!'" The singer added that Silas likes golf but he doesn't want to pressure him too hard to be into the same things as his dad. "He's fast and he's active, so he's very good at tennis."
Despite having two famous parents, Silas, apparently, isn't fazed by their many accomplishments. While on "The Tonight Show Starring Jimmy Fallon" in May 2021, Biel shared that Silas is familiar with his father's music but has a nonchalant attitude toward it. "Whenever he hears Daddy's song, he'll go, 'Oh yeah, that's Dad. No big deal, whatever,'" she recalled.