Jessica Biel reveals her No. 1 parenting 'hack' with son silas (Exclusive)

Jessica Biel is opening up about her favorite and most trusted "mom hacks" when it comes to raising her and Justin Timberlake's 3-year-old son, Silas.

ET recently caught up with the actress at Au Fudge restaurant in West Hollywood, where she was joined by renowned pediatrician Dr. Harvey Karp -- creator of the SNOO Smart Sleeper baby bed-- and Biel explained how she first looks to her family for support and help.

While she used to rely on a variety of different gadgets and gizmos tailored to make parenting at least somewhat easier, now that Silas is getting older -- and with Timberlake on the road for his Man of the Woods Tour -- Biel says she's been turning to a different "mom hack" -- her mother.

"The hack we use now [is] Grandma," Biel shared.

Biel recently shared her gratitude with her mom, Kimberly, on Instagram in a heartfelt Mother's Day post, in which she acknowledged everything her mom sacrificed for her.

"It took me almost thirty years to truly understand everything you sacrificed for me. I am in awe of your wisdom and grace, and I hope I can emulate those ideals with my own child (without ending up in a straitjacket)," she captioned a photo of herself and her mom enjoying wine and mimosas at brunch."

Biel joked about the photo with ET explaining that, despite appearances, they didn't have too many mimosas between the two of them, because, even on Mother's Day, moms are always "still having to hang out with these small people."

"That's the funny thing about Mother's Day -- you're still doing what you have to do every day, for the most part, it's just a little bit sweeter because you have a great brunch you have mimosas and you have some flowers," she explained.

For Mother's Day, Timberlake flew home between tour stops, having played in Duluth, Georgia, just days before, then jetting off for his show in Orlando, Florida, the next day.

Biel dished on her husband's new national tour -- which runs through Jan. 29, 2019 -- and admitted that, despite having seen him perform countless times, she's still floored by each show.

"One of the best parts, I think, of being on tour is seeing someone react to the show who's never seen the show before," she shared. "Because I've seen it a lot of times and even still it's absolutely awe-inspiring every time."