Peter Facinelli And Lily Anne Harrison Welcome First Baby Together On Labor Day

It was truly a "labor day" on Monday when Peter Facinelli and fiancée Lily Anne Harrison welcomed their first baby together. The "Twilight" star, 48, posted the happy announcement on his Instagram page captioning the black-and-white photo, "Happy “Labor” Day @lilyanneharrison ❤️ Sept 5th, 2022 🍼👶🏼."

This is the first baby for Harrison, 33, and the fourth for Facinelli who shares three daughters, Luca, 24, Lola, 19, and Fiona, 15, with ex-wife Jennie Garth. Harrison first announced her pregnancy in June on her Instagram page with a selfie captioned, "Not a burrito belly 💗" A sea of congratulations filled the comment section. Facinelli jokingly commented, "You’re pregnant? 😳 Why didn’t you tell me?"

Just a few days later, Harrison followed up her original announcement with a full-length "bump" selfie captioned simply, "✨✨✨."  A few more bump snaps were posted following her pregnancy journey with the final pregnancy shot posted just three days before the baby's arrival captioned, "And the countdown begins ⏳."

The couple have been together since September 2016 and got engaged on New Year's Eve in 2019 while vacationing in Mexico. The actor proposed at a romantic beach dinner and were joined by Facinelli's three daughters and Harrison's parents. Facinelli talked to PEOPLE last October about his wedding plans. "I want [our wedding] to be in a world where there's no masks. There's no rush for us. We're devoted to each other and we're living a life together," he explained. "I already feel married. We have everything besides the piece of paper and the party!"

The actress posted about her engagement captioning a photo of her on the beach sipping champagne, "Bye 2019 🥂 thanks for kicking my butt, making me stronger than ever, protecting my family and hurtling me toward my dreams ✌🏻also, not a bad way to ring in the new year with my sweetheart 💕 #estrelladelmar #mazatlan @peterfacinelli" Facinelli also posted a similar pic captioning it, "“A Magical night with this incredible woman. A Perfect ending to 2019.”

This is Facinelli's third engagement and will be his second marriage. Facinelli was also engaged to "Blindspot" actress Jamie Alexander after dating on-and-off for many years. It was confirmed that the two had split in February 2016.

Facinelli and Garth divorced in 2013 after 11 years of marriage, but have continued to successfully co-parent together. In 2017, Facinelli told LaPalme Magazine that their co-parenting plan is driven by "love and respect." He also said, "We talk all the time about co-parenting and the kids." The two exes have remained friendly and even vacationed together with their daughters, Harrison and Garth's husband Dave Abrams in 2017. An onlooker during their vacation together told PEOPLE, "The group seemed happy, like a modern family. The adults would look to each other to provide cover for one another when the kids were plunging into the pool and gleefully splashing them."