In just eight weeks, John Stamos has transformed from America’s favorite uncle on Full House to everyone’s favorite new dad.
The actor, 54, is now a proud father to son William “Billy” Christopher, with wife Caitlin McHugh. And not even two months into parenthood, Stamos is revealing to PEOPLE how he’s been adapting to the spit-up and tears — the latter of which he admits haven’t only been coming from his newborn.
“It’s been beautiful,” he tells PEOPLE for this week’s issue of his first weeks as a dad. “Every second you pray that you can keep the kid alive. Every day is different, time has become very elusive, stuff just goes by so fast. It’s just beautiful. I’ve cried most days; I just stare at him.”
Unfortunately, Billy hasn’t quite picked up on Stamos’ iconic haircare regimen just yet — but the new dad says his son has inherited his signature smile.
“He has my smirk,” Stamos shares. “But he only goes into action when I turn off the camera! I’ll have to reverse that if he’s going to be my son.”
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The star, who recently designed a “St. Amos” bracelet collection with McHugh, 32, for My Saint My Hero, also says that aside from his sleep schedule, his style has changed as well.
“I went to a meeting with spit-up milk on my knee and my shirt was wet still from pee. That’s my style,” he admits. “I’ve really neglected myself. In fact I’ve really got so gosh darn fat! I’m going to Pilates right now.”
Continues Stamos, “People over the years have said, ‘Wow, you look so young!’ Get ready, folks, ’cause now I’m going to show them I look my age and I’m older.”
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Another upcoming milestone for Stamos? His first Father’s Day on June 19, which he says he plans to spend thinking of his own father, whom Billy is named after.
“I know I’ll be crying a lot,” he says of his plans for the holiday. “I’ve been writing Billy a letter that I’m putting away for him to read when he’s 18. I’ll probably continue writing that, and I’ll certainly try to honor my father.”
As for little Billy, Stamos hopes to do what he can to help make the world a better place by the time his son grows up — and he’s starting by spreading the love through his new bracelet collection.
“We live in an anxiety-riddled, unsure, divisive time right now,” says the ER alum. “I think most of us are searching, even subconsciously, to find what’s missing from our lives: grace, charity, kindness, and peace, and family, and community and friendship.”
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“I just hope this world is a better place for Billy when he starts to understand what it’s all about,” Stamos explains. “And I just want to be an example to him. I have a real responsibility now. I’ve never really had real responsibility.”
He adds, “I thought it was beyond me to have a kid and a great wife, but it’s given me a reason to live. Life is in session now.”
For more from John Stamos, pick up this week’s issue of PEOPLE, on newsstands now.