“Presley is just a name I’ve always loved,” the former Twilight star, 31, tells PEOPLE. “It’s kind of rockabilly, a little bit of my Southern roots and heritage. And Bowie is a family name from my mother’s side. And I’m also a fan of David Bowie, so it’s a tribute.”
“Having a boy first and then a girl, I think it’s going to make [Monroe] a better man when he grows up,” says Rathbone, who adds that his son has been “the sweetest big brother.”
“Whenever we want to change a diaper, he wants to help, and he gets us a diaper, and he’ll get the wipes if we’re in a different room,” the actor and musician continues. “He likes to hold her and give her kisses, tell her goodnight.”
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Even though Presley — whom Rathbone describes as “very relaxed” and “chill” — is only 7 weeks old, she’s already reached a sweet milestone.
“Last week, she gave Mama a smile with a big face of dimples,” the proud dad says. “I think it was just because she had a big meal. Whenever I have a big meal and I get to take a nap, I smile too!”
While adding another member to the family has been challenging — “There’s no such thing as easy when it comes to dealing with kids!” says Rathbone — he’s also been enjoying the new dynamic.
“It’s been fun too,” he says. “Monroe likes it because it’s like, the boys are going to go — ‘Daddy and I are going to go do this, and the girls are going to go do this.’ I love it. It’s so nice to have a boy and a girl. It’s our little family of four.”
Will the Rathbones become a family of five down the line?
“We’re going to take some time,” says Rathbone. “In a hypothetical sense, sure, why not? We’re open to multiple ways of having kids.”
— Gabrielle Olya