In the adorable photo, Phoenix looks like he has angel wings as he lays peacefully in blue and white striped pajamas next to blocks that spell out “2 Months.”
“2 months and counting……#phoenixrobertlachey,” Nick, 43, captioned his post.
Vanessa, 36, simply wrote: “My Phoenix” with two blue hearts.
“Right now he’s [a] newborn, so it’s more about Mom than it is about Dad,” Lachey told PEOPLE about baby Phoenix in January. “But the cool thing about that is it’s given me a lot of time to spend with the other two and pal around with Camden and Brooklyn.”
Three has always been the magic number when it comes to kids for both Nick and Vanessa.
“[My wife Vanessa] and I always, in the back of our minds, wanted three kids. So here we are at three, and it’s awesome,” Nick said.
Though they’ve reached their goal, that doesn’t mean they necessarily will be capping their family expansion anytime soon.
“Short of a surgical procedure, I guess it’s always an option, but I’ve given up on trying to predict these things,” joked Nick. “Apparently there’s a way to make babies and we’re fairly good at it, so you never know. But I think right now, three feels like a very good number.”
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Now a father to two sons and a daughter, it’s no surprise that Nick has wisdom to impart when it comes to parenting.
“What’s really cool is they’re all so different in their own ways, and you don’t really see that until they start to get older and get their personality,” he said about his kids. “But they’re all so unique and different, and you love the different things about them in different ways.”