The two had celebrated Christmas early with her family, including her parents Billy Ray Cyrus and Tish Cyrus, earlier this week. On Friday, they partied with Liam's brother Chris Hemsworth and his wife Elsa Pataky.
Liam posted on his Instagram page a selfie of him and Miley wearing zany, red and green Christmas sweaters. Miley also sported a red and green light-up bow in her hair and a necklace of colorful lights.
"Happy birthday Jesus," the actor wrote.
Elsa shared on her Instagram page a photo of her and Miley embracing.
"Fun Christmas Party with my family!" she wrote. "Fiesta de Navidad con mi family!!! Happy Christmas! Feliz Navidad!"
The Spanish model and actress also posted a pic of Chris kissing her. She is wearing red pants with a white trim and a dark shimmering halter crop top, while the Thor star sports red and white pajamas.
"Best Christmas present ever! A kiss from @chrishemsworth !!!" Elsa wrote. "El mejor regalo de navidad!!' Un beso de de @chrishemsworth!!"
In fact, Liam has been more active on the social network in general and the two have shared more photos of themselves together more since they got back together.
In October, they made a rare public appearance together, attending the Variety's Power of Women luncheon, where Miley was honored.
In November, Miley and Liam attended his and Chris' brother and Westworld actor Luke Hemsworth's '80s-themed 36th birthday party.