Biel and her husband welcomed baby Phineas last summer after a private pregnancy. On "The Ellen DeGeneres Show," the "7th Heaven" alum -- who is currently an executive producer on Freeform's new mystery series "Cruel Summer" -- shared that she and Timberlake are currently sleep training Phineas, which means spending a lot of time listening to a teething, crying baby.
"It's so hard to let them cry for even a few minutes. That's the sleep training we were doing. Phin did a beautiful job," Biel explained in an episode set to air Monday, April 19. "We never really followed through with Silas in a big way with the sleep training. I think it was because he was a first child, we were nervous, we couldn't bear the thought. Now it's like, 'Yeah, yeah, yeah, you're going to be fine. You're going to make it. You'll be OK.'"
When asked if having two kids is harder than one, Biel confirmed that it's definitely not easy.
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"A very wise friend of mine said, 'One is a lot. And two is a thousand,'" "The Sinner" actress joked. "That's exactly the way it feels. You're like, man-on-man defense, one person's here, one person's over there. It is a wild, wild ride."
There is a silver lining to the chaos, Biel explained: the adorable bond between her two kids.
"It is so cute to see these two together," Biel shared. "They both think the other one is hilarious. Silas, he is the performer, he wants to make the jokes and he wants all the attention on him, so Phin only has eyes for him. Everything that Silas does is hilarious and then anything that Phin does is hilarious. So they just laugh at each other all day long."
Last year, Biel and Timberlake spent the majority of their time in Montana, away from the hustle and bustle of Los Angeles.
"It's been a great break for them, with a lot of family time and adjusting to life with two kids," an insider shared with E! News at the time. "Justin and Jessica have their hands full with the kids, but they are both super active and love to golf, play tennis, hike and snowboard."
As for Silas and Phineas, however, they don't need much to entertain them -- just one another.