Celebrity Parents Jessica Biel's Son Silas, 6, Has Chill Response to Justin Timberlake's Music: 'Oh Yeah, That's Dad' Jessica Biel and husband Justin Timberlake have two sons, Silas and Phineas By Ally Mauch Published on May 8, 2021 10:45AM EDT Jessica Biel's oldest son is unfazed by having famous parents. The actress, 39, appeared on The Tonight Show Starring Jimmy Fallon on Friday and revealed that while her 6-year-old son Silas recognizes dad Justin Timberlake's music and acting, she can't get him to watch her own children's show, Pete the Cat. "Do they kind of freak out because their dad is in Trolls, their mom is in Pete the Cat, they hear these voices and they go 'wait what's going on?' Do they understand what you guys do?" host Jimmy Fallon asked, referencing Silas and the couple's younger son, Phineas. "Silas does definitely with Justin because of Branch," Biel said, noting Timberlake's character in the Trolls movie series. "And also his music — whenever he hears daddy's song he'll go 'Oh yeah, that's dad. No big deal, whatever.' " Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories. Jessica Biel and Justin Timberlake with son Silas. Justin Timberlake/Instagram Justin Timberlake and Jessica Biel. Rodin Eckenroth/Getty Jessica Biel Says Sons Phineas and Silas Think Each Other Are 'Hilarious' She continued, "But the funny thing about Pete the Cat is I tried to get him to watch the show, he will not watch. And yet he says 'hey mom, hey mom, do one of those voices from the show' and I'm like 'But you've never seen the show you don't even know.'" "He's just like 'just do it mom,' so I'll do one of the voices and he'll be like, 'cool mom, cool,'" Biel recalled, laughing. NBC Justin Timberlake Wants Sons to 'Be Kids for as Long as Possible' Without Being 'Weirdly Private' Earlier in the interview, Fallon, 46, asked whether the actress thinks the two boys are "besties." "I think they are, I really do and I really was worried you just never know what's going to happen and how your older one is going to feel about the little one," Biel said. "Just think each other are so funny, and it's so amazing to watch." Want to get the biggest stories from PEOPLE every weekday? Subscribe to our new podcast, PEOPLE Every Day, to get the essential celebrity, entertainment and human interest news stories Monday through Friday. Timberlake, 40, first confirmed he and Biel welcomed a second child during a January episode of The Ellen DeGeneres Show. "He's awesome and so cute," Timberlake said of the couple's new addition. "Nobody's sleeping, but we're thrilled. We're thrilled and couldn't be happier. Very grateful."