Catherine gave birth to their third child on Monday, December 23. They shared the big news via social media. The happy parents posted photos on Instagram of both mother and father holding their newborn, Mia. Sean captioned a picture of himself, “I’ve always wanted a daddy’s girl and now I’ve got her. Mia is healthy, Mama is doing great, and God is so good!”

Catherine posted a photo from her hospital bed and wrote, “Mama, Mia.”

Bachelor Nation friends flooded their comments section with support. Chris Harrison wrote, “God bless brother. Congrats!”

Ali Fedotowsky-Manno added, “Awwwwwww so exciting!!!!!! Congratulations mama and Mia!!!!!”

Sean teased the baby’s imminent arrival on Twitter and Instagram early in the day. He posted photos with son Samuel and captioned one, “Starbucks with my dude before baby comes.” He also sent out a bunch of lighthearted tweets over the course of hours, including one that said, “I’m going to be a father today! For the 3rd time in 3.5 years!”

He later quipped on Twitter, “Hospitals should really have a punch card system for frequent customers. 3 and it’s free kind of thing.”

The family celebrated Christmas early at home because they knew they’d be in the hospital on the actual holiday. Sean and Catherine both posted photos from their early festivities before becoming a family of five.

Catherine captioned a picture of the four of them in matching pajamas, “To ensure that I don’t have serious FOMO while spending it in the hospital on actual Christmas, we had our Christmas early. Plus, what do these kids know anyway. (Answer: Nothin’)”

As “The Bachelor” couple eagerly awaited their baby’s arrival, Catherine wrote several posts about overcoming fears as a mom and providing her children with as much love as possible. She captioned a selfie of sons Samuel and Isaiah kissing her baby bump, “When Sean and I first talked about having a family, we constantly talked about a house full of love and laughter. I don’t think the baby knows how much love is really in store for him/her.”

In October, the Seattle native opened up about her “biggest fear” about motherhood and how that changed when she gave birth for the first time. Catherine wrote, “My biggest fear before having Samuel was that I wouldn’t be naturally maternal. Not the pregnancy pains or the delivery unknowns or the sleep deprivation everyone talked about. That I wouldn’t be the mother he needed because I didn’t think I had the motherly instincts.”

Her note continued, “Now, I’m 7 months pregnant with my third child and I cannot wait to share all the love I know I have to offer him/her,” she wrote. “It comes on strong, people and I know it will never leave. My heart has grown to annoyingly adore each one of my sweet babies.”

Catherine and Sean told People in their pregnancy announcement that the news caught them off guard. She told the magazine, “It was a complete surprise, and I stared at the wall for a good 24 hours. “I was like, ‘I just had one of these!’”

She said it all felt “overwhelming,” but she and Sean want “a big family.” Catherine shared, “This is just the way it was supposed to happen. So we’re excited.”