Bristol Palin shares adorable photo of Trig and Sailor

Bristol Palin shared an adorable photo on Instagram of her little brother, Trig, snuggling up to his new niece, Sailor.

Bristol, 25, welcomed her daughter on Dec. 23. In the Instagram snap, Trig is kissing Sailor on the forehead; Bristol wrote, "Trig officially loves her." She also included the hashtag "#mybrotherhasmorechromosomesthanyou."

The hashtag refers to the fact that Trig, 7, has Down syndrome. He is the youngest child of Sarah and Todd Palin.

There's plenty of love to go around for Sailor: Bristol's son Tripp definitely loves his sister as well. The proud mom has posted photos of Tripp holding and doting on his sister.

Sailor's birth hasn't exactly been drama-free, though. Her ex-fiance Dakota Meyer has filed for joint legal and physical custody of the baby, along with child support, reports ET.

Earlier this month, Sarah Palin gave a statement to ET saying, "For many months we have been trying to reach out to Dakota Myers [sic] and he has wanted nothing to do with either Bristol's pregnancy or the baby."

But if Bristol is worried, it isn't showing on social media. She has posted several of happy photos of herself with her friends and her kids since Sailor's birth.