Lori Loughlin is loving cuddling "Billy the Kid," her longtime friend and costar John Stamos' 5-week-old son with wife Caitlin

By Jen Juneau
May 17, 2018 05:05 PM

Lori Loughlin is spending time with John Stamos’ baby — and loving it!

The Fuller House star — who plays Rebecca Donaldson-Katsopolis to Stamos’ Jesse Katsopolis on the series and its predecessor Full House — is gaga over the actor’s newborn baby boy William “Billy” Christopher, sharing a snapshot of herself cuddling the adorable 5-week-old.

“Move over @johnstamos there’s a new kid in town!” Loughlin jokingly captioned the tender post on Wednesday. “Billy The Kid and he’s already stealing ❤’s! #iminlove

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Baby Billy has already met multiple members of the Full House family since Stamos, 54, and his new wife Caitlin welcomed him into their lives on April 10.

Last week, the actor shared a photo of an adorable moment on Instagram where he held Billy in his hands as Loughlin, 53, and Bob Saget bent over him and smiled.

Billy, whose back was turned toward the camera, wore a black onesie that read “Jesse and the Rippers,” a reference to the band that Stamos’ character Jesse plays in.

RELATED VIDEO: New Dad John Stamos Opens Up About Fatherhood and Reveals Which Parent His Son Looks Like

Loughlin — herself a mom to daughters Olivia Jade, 18, and Isabella Rose, 19 — raved about her TV husband in February, telling Megyn Kelly during an appearance on Megyn Kelly Today of Stamos, “He will be a wonderful dad.”

“We’re [still] very good friends. He got married,” she continued, adding of the 32-year-old model and first-time mom, “[Caitlin]’s a wonderful girl. She’s really good for him and I’m very happy for him.”