“He was Baby Doe for the first three days,” Holliday, 31, tells PEOPLE. “We wanted him to have a name that no matter what kind of person he grew into, it would suit.”
Bowie’s dad felt the name was a perfect tribute to the late David Bowie, whom he had long admired.
“David Bowie was really important to me because he was the first person that showed me that there was a different way of being a man,” Nick, 31, says.
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The name Juniper grew out of Nick’s love for flower names.
“I think they’re beautiful for girls, and there’s not a lot equivalent for men, so I literally just went through a list of botanicals and Juniper was on the list,” he says.
“We thought it suited him because he has such a sweet temperament,” adds Holliday.
“I feel like he willed it to the gods,” jokes Holliday. “But I can’t imagine him not being here. We’re really happy.”
Although Bowie is less than two months old, he’s already reached an adorable milestone.
“He started smiling a week ago!” says Holliday. “If you talk to him, or tickle his cheek or his little nose, he’ll smile. You can be having the worst day and he’ll make his little smile and I’m so happy.”
So far, having a newborn has been relatively smooth sailing for the Los Angeles-based body-positive activist.
“I feel like we got lucky,” she says. “People always say terrible things to you when you’re pregnant, like, ‘You’re never going to sleep!’ He’s been sleeping for about six hours a night. It’s so nice! He’s such a sweet, chill guy.”
The biggest challenge has been trying to divide her time between Bowie and Rylee.
“It’s harder in just trying to make sure that I’m giving both my kids attention and paying attention, and constantly telling Rylee, ‘We love you just the same,’ ” she says. “That has been really challenging.
“But I feel more comfortable this time because I’ve done it before, and I feel more confident in my skills because Rylee’s still here so I obviously did something right!” she continues.
Bowie already shares some of Holliday’s physical features — “I think he has my nose, and he definitely has my lips,” she says — and even is starting to emulate his big brother.
“He pouts, which Rylee used to do too,” says Holliday. “I have a lot of photos of Rylee poking out his bottom lip, and he pokes his lip out too.”
So are more babies on the horizon?
“I think I’m definitely open to having another one, but maybe planning the next one a little better,” says Holliday.
“This was a surprise,” adds Nick. “Any one that’s not a surprise would be nice!”
For more from Tess Holliday, pick up the latest issue of PEOPLE, on newsstands Friday.
— Gabrielle Olya