Bristol Palin has welcomed her second child, baby girl Sailor. Credit: Eugene Gologursky/Getty Images

Bristol Palin has welcomed her second child, a little girl. Sarah Palin's daughter announced the news on Instagram on Thursday, December 24, sharing a pic of her newborn and her son, Tripp.

"My heart just doubled," she captioned the sweet black-and-white snap.

She also shared a photo of herself cradling her newborn, writing, "My sweet Sailor Grace was born yesterday, our family couldn't be more complete."

The Dancing With the Stars alum, 25, revealed in June that she was expecting, just one month after ending her engagement to Marine Dakota Meyer. (The couple called it quits one week before their nuptials.)

My sweet Sailor Grace was born yesterday, our family couldn't be more complete 💕

A photo posted by Bristol Palin (@bsmp2) on

My heart just doubled

A photo posted by Bristol Palin (@bsmp2) on

Meyer also shared a pic of Sailor on Facebook, writing, "Best Christmas present ever!! I could not be more proud of this little blessing."

Best Christmas present ever!! I couldn't be more proud of this little blessing.

Posted by Dakota Meyer on Thursday, 24 December 2015

Last month, Bristol posted adorable monogrammed outfits she had made for Sailor. She decided to reveal the name after Kristin Cavallari welcomed her own daughter named Saylor.

"When you find out @kristincavallari named her baby the exact name you are naming yours. What a weird coincidence," Bristol joked via Instagram. "Congrats on your new bundle, and I do love her name.. Still naming my baby girl Sailor!"

The Alaska native is already mom of son Tripp, 6, who she had with ex-fiancé Levi Johnston. (Johnston, 25, married his girlfriend Sunny Oglesby in October 2012. They are parents of daughters Breeze, 3, and Rae, 10 months.)

Bristol more recently posted an adorable photo with Tripp via Instagram on November 26. "Happy Thanksgiving," she captioned the pic. "Thankful for my babies."

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