Peter Facinelli on Turning 50 and Raising a 1-Year-Old: ‘I Remember How to Change a Diaper’ (Exclusive)

After raising three daughters who are now grown, Peter Facinelli is doing fatherhood “all over again” with fiancée Lily Anne Harrison

Peter Facinelli has had to relearn a lot while parenting a 1-year-old — except for one important skill. “Yes,” he confirms, “I remember how to change a diaper.”

It’s been a while since Facinelli, 49, last had an infant to care for. The Nurse Jackie and Twilight actor shares three daughters with ex Jennie Garth: Luca, 26, Lola, 21, and Fiona, 17.

Since Facinelli and his fiancée, actress Lily Anne Harrison, welcomed their son Jack on Labor Day 2022, he’s been relishing another round of fatherhood. “It's just a real treat to be able to do it all over again,” Facinelli tells PEOPLE exclusively.

“He's got such a great personality and he's so smart,” he says of little Jack.

“He just started walking,” he adds. “Now he's teetering all over the house. He's like a little drunken sailor. I'm there to pick him up when he falls.”

Of course, Luca, Lola and Fiona shower their new sibling with love. “They came to his birthday party,” says Facinelli with a smile. “It was really, really cute to see them all together.”

He’s beyond proud of his adult and teenage daughters, he adds. “They give great advice. So I know I did something right when they give me great advice.”

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Does becoming a father over two decades ago give Facinelli a headstart on raising Jack? “I think each kid is different, and every time you have a kid, you're growing and learning with them, so it is different,” he says.

Among the lessons learned this time around is patience. “Children always teach patience. For me, when you have a kid and their energy is crying or screaming, as a parent, you take on that emotion because it's hard not to get stressed out.”

“But it's really a lesson in, if you can keep calm yourself and just be there for them and observe, they'll take on your energy.”

It’s a philosophy that serves Facinelli well in his line of work as an actor and filmmaker. “Somebody is angry and you want to match that energy,” he says, “and sometimes remaining calm and allowing them to get it out, then all of a sudden, they start to match your energy.”

He adds, “It's a beautiful thing having kids, because they teach you relationships. We're all children on the inside… just children in a grown body.”

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Facinelli now stars in the indie thriller On Fire (in theaters now) which he also co-directed. And as Jack’s first big milestone passes, another appears on the horizon: Facinelli turns 50 this November. 

“It's just a number!” he laughs. “I've always felt like you're as old as you feel. My dad still moves around like he's in his forties — he's got a young heart.”

Facinelli isn’t sure yet how he’ll ring in the big 5-0, other than “a celebration of my years on Earth.” A raucous evening of friends dressed as Peter Facinelli characters, perhaps, or quiet time in with family, he says.

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Harrison is “an incredible mom and partner,” he adds, and they’re in no rush to get to the altar. (The couple has been engaged since New Years’ Eve 2019.)

“We'll get to the party and the piece of paper, but for me, the more important thing is the living and breathing relationship of marriage. And that, I live every day.”

All that’s certain about Facinelli’s new chapter is that he’s approaching it with the same characteristic attitude of gratitude that’s enabled him to balance a thriving film career with parenthood. “I’ve been telling stories for a living for 30 years,” he says, “so hopefully I can do another 30.”

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