Congrats to Catelynn Lowell and Tyler Baltierra, who welcomed a child on New Year's Day!

The 'Teen Mom' stars shared their excitement over baby Nova Reign on social media. Tyler tweeted the news, telling fans, "OMG guys, my daughter is BEAUTIFUL! Can't wait for you guys to see her! Born on 1/01/15 at 3:15 #StillCantBelieveIt #ShesPerfect."

Shortly afterward, he shared a photo of Catelynn and their daughter on Instagram. You can check out the sweet snap below. Awww, our hearts are melting!

'Teen Mom' fans remember Catelynn and Tyler's difficult struggle in 2009's '16 and Pregnant.' They bravely decided to give their firstborn, Carly, up for adoption. They later appeared on 'Teen Mom,' where fans continued to watch their story evolve.

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