Everywhere you look, there's a new congratulatory message for Ashley Olsen. 

And John Stamos is the latest member of the Full House family to celebrate following reports that the actress—who along with her twin sister Mary-Kate Olsen played Michelle Tanner on the '80s-to-'90s sitcom—welcomed her first child with husband Louis Eisner.

"Watching Mary-Kate and Ashley grow into the incredibly bright and remarkable women they are today has been one of the greatest joys of my life," the actor, who portrayed Michelle's uncle Jesse Katsopolis on the show, wrote on Instagram Aug. 24. "If you would have told me those blue-eyed babies I met on set nearly 40 years ago would still be in my life at 60 years old, I wouldn't have believed you. I am blessed. Congratulations to Ashley and her husband, Louis, who welcomed their baby boy last week."

Along with the message, John included a video montage featuring throwback footage of him, Ashley and Mary-Kate as well as an audio recording of him reading a passage from his upcoming memoir If You Would Have Told Me.

In the voiceover, he recalls how the last casting call was for Michelle—the youngest daughter of the late Bob Saget's character Danner Tanner—and how the part went to Mary-Kate and Ashley, who had "big blue eyes wide with wonder." 

"Right away, I know the relationship between Jesse and Michelle is an important one," John reads. "But as the show develops, the connection grows. I'm young, but I really want kids someday. And these lovely little girls—so bouncy and bright—represent the best versions of future dreams."

The General Hospital alum—who would welcome son Billy, 5, with wife Caitlin McHugh in 2019—then further elaborated on how his bond with the twins influenced his hopes for his own family one day.

"They allow me to consider fatherhood like a benched baseball catcher in a dugout—watching from afar but not having to catch any curveballs," he continued. "I take them to Disneyland, I adore them—giving them kisses on top of their heads, buy them a few crappy souvenirs and then hand ‘em back to their parents to do the hard work. The little kids that were supposed to be background noise grew up to be the kind of humans I hope to have one day. They are precious, delightful and bright. I adore them."

John isn't the only Full House star to congratulate Ashley. Jodie Sweetin, who played Michelle's sister Stephanie Tanner, and Andrea Barber, who portrayed their neighbor Kimmy Gibbler, did too.

"The baby had a baby," Jodie said on the Aug. 22 episode of their podcast How Rude, Tanneritos. "I'm sorry, I know she's not a baby. She's a 37-year-old woman, I realize that. But it's like when the youngest member of your family has a kid. All of a sudden you're like, 'Oh my gosh it's happening!' So yeah congratulations, Ashley and her husband I'm just really, really happy on the birth of their baby boy Otto. I'm sure that they will keep it very private, as they do, but I just want to wish them well and congratulations and welcome to motherhood."

E! News has reached out to Ashley and Louis' rep for comment on the baby news but has yet to hear back.

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