Photo: Emmalee Mang; Inset: Alberto E. Rodriguez/Getty

john stamos

John Stamosis getting an early start on his son’s birthday celebrations.

On Wednesday, theFuller Housestar shared a series of photos onInstagramfrom the festivities in honor of his sonBilly, who turns 4 on April 10. For the occasion, they visited Discovery Cube’s Bubblefest where Billy was all smiles as he played in the room full of bubbles.

“Celebrating early “Billy Birthday"courtesy of his beautiful auntie@alainastamosand@thediscoverycube- We LOVED#bubblefestTHANK YOU for a Wonderful Day!” the proud dad captioned the post.

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PHOTO: Emmalee MangPHOTO: Emmalee MangPHOTO: Emmalee Mang

john stamos

john stamos

john stamos

Back in September, theBig Shotactor mused overhow fast his son is growing up, sharing an adorable slideshow toInstagramof Billy on his first day of school.

The video, set to The Beach Boys track “When I Grow Up (To Be a Man),” included several photos of Billy throughout his childhood. In the last picture, the toddler smiles on his first day of school, wearing a blue Hawaiian shirt, navy shorts, Adidas sneakers and carrying a colorful lunchbox.

“First day of school. I’m not crying, you are,” Stamos wrote.

Stamos also spoke to PEOPLE last summer aboutlife at home with his little boy, calling his family of three a “dream come true,” especially considering the actor once believed having a family wasn’t in the cards.

“I always wanted to have kids, but I didn’t think I’d meet the right person,” Stamos recalled. “And maybe I felt like well, I have everything, I shouldn’t be greedy.”

Ultimately, Stamos said he attributes finding his wife to “straightening up my life.” Said the actor: “I wasn’t deserving of it yet I think. But six years ago, I sobered up and I became a better person. And when Caitlin came around, I recognized it immediately. I said, ‘I have to be good for that to make it work.’ "

source: people.com