Lachey, party of five!

Vanessa and Nick Lachey announced on Monday, December 26, that they welcomed their third child, a baby boy named Phoenix Robert, on Christmas Eve.

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“It's a very Merry Christmas indeed! We had our Christmas Miracle. Phoenix Robert Lachey decided to show up early and was born on Christmas Eve. Mommy, Daddy, Camden & Brooklyn LOVE You very much!” the proud mom wrote next to an Instagram photo of her newborn son’s hand grasping her fingers.

The couple — who also share four-year-old son Camden and daughter Brooklyn, 23 months — announced the pregnancy back in September.

“We got a new crib! Now we need a new CRIB. Newest Lachey arriving Spring 2017,” Nick posted, along with a pic of his beautiful family.

Vanessa later announced that they were expecting a boy after surprising her hubby with an array of blue balloons in their home.

"I have so much to be thankful for this year, especially our littlest Lachey. When Daddy came home from tour this summer and we were moving into our new house I shared the news! Now I'm sharing it with you!” the 36-year-old brunette beauty said at the time.

“I am so very thankful and grateful for this family of mine! And thankful for YOU! All your love and support makes what we do FUN and worth it!"

Nick, 43, has been known to gush about fatherhood. “It’s just all-encompassing. You would do anything for your children — not that you wouldn’t for your wife or someone else you love, but there’s a sense of protectiveness and responsibility that comes with your child, which you don’t feel in any other relationship,” he previously admitted. “[Becoming a dad] has changed my life in every possible way.”

We’re thrilled for the duo! Scroll through the gallery below to see more celebrity babies who made their debut on social media in 2016.