Teen Mom's Javi Marroquin and Girlfriend Lauren Comeau Welcome Baby No. 2: 'Sissy Is Here'

Javi Marroquin's family has grown by one more!

The Teen Mom 2 alum, 31, and his girlfriend Lauren Comeau have welcomed their second baby together, a daughter, sharing the news in a joint Instagram post.

In the photo, Marroquin and Comeau can be seen holding their newborn daughter in seven different Polaroid photos, one of which features Marroquin's son Lincoln, 10, whom he shares with ex Kailyn Lowry.

Marroquin and Comeau's son Eli, 5, can also be seen in the family photo, grinning in between his siblings. "Sissy is here! 💕 Our sweet sister girl arrived last night & we are all head over heels in love 🥰," the couple captioned their post.

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In December, Marroquin and Comeau announced they were expecting their second baby together, announcing the news on Instagram.

"Christmas came early & we got our sweetest wish 💖," the caption read. "Little sister coming this summer & we couldn't be happier 🫶🏼."

In November, both Marroquin and Lowry celebrated Lincoln on his 10th birthday.

"HAPPY 10th BIRTHDAY to the big dawg! A decade…wow! I love you so much and am so proud of who you are. Cheers my boy 🎈🎈🎈," the proud dad captioned photos shared on Instagram.

On her own Instagram, Lowry shared photos from Lincoln's basketball-themed birthday party with her, writing, "There’s something about this one 🥲 he makes me so proud. 10?!? where does the time go? #10 HAPPY BIRTHDAY TO MY BABY! 💙🏀."