Jessica Biel Shares 'Magical' Motherhood Moment

Four months after she and Justin Timberlake welcomed their son Silas, Jessica Biel stepped out for a red carpet event — and opened up about the joys of being a mum.

Describing the best thing about motherhood (so far, anyway), the Total Recall star didn't hesitate.

"Probably the moment he wakes up from a nap," she told E! Online.

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"He's sort of looking around and you sort of creep up and look over the crib and he looks up and he goes [Biel lets out a big sighing sound]. Just a gummy mouth, no teeth, just a big smile, happy that you're alive and you're just looking at him. That's probably the most magical."

But like so many special moments, however, this one doesn't usually last too long.

"You quickly move on from it because there's a dirty diaper in your palm," the 33-year-old mused at the celebration for the latest collection of Bare, an eco-accessories line she launched with her brother, Justin Biel, and designer Grason Ratowsky. (The line doesn't yet offer a diaper bag — possibly because Ratowsky isn't keen on the word "diaper" — so Biel is hunting for a new name to encourage the designer to embrace the mommy must-have.)

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Though her husband hasn't said much about fatherhood just yet, Timberlake did share an Instagram of himself with Silas in his arms on Father's Day along with a heartfelt message.

"FLEXIN' on Fathers Day," the 34-year-old singer captioned the adorable shot. "#HappyFathersDay to ALL of the Dads out there from the newest member of the Daddy Fraternity."

On Wednesday night, Biel was backstage at Taylor Swift's final show at the Los Angeles Staples Center to watch her better half perform his 2013 hit song, "Mirrors." Baby Silas did not attend the event, but Biel's mother reportedly did.

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"It was super fun," Biel recalled of the night out (though she left shortly after her hubby performed). "We are fans of music from all walks of the spectrum, from country to rock to R&B to hip hop, whatever. I'll pretty much see anyone live."

For now though, it seems that the person the actress most wants to see is her son.

Elizabeth Durand Streisand writes for Yahoo Celebrity