Molly's boyfriend Joel popped the question, but instead of sharing photos of the happy couple on social media, Molly posted photos of herself celebrating the big news with her parents.
Molly, 23, shared two photos in which she was showing off her new diamond engagement ring Thursday on Instagram -- one with her mother and one with her father.
Molly sat on her dad Matt Roloff's lap in one picture, while she beamed a huge smile in the other image with her mother Amy Roloff.
Amy shared her daughter's photo on her own Instagram account the same day with the following sweet caption: "My baby girl. My best birthday gift ever (we share same bday) My Molly girl... is home for Christmas AND she is engaged to be married. Woohoo! So happy for her."
"Joel is one lucky man to capture her heart," Amy continued. "Yes he's a great guy. Love Love her forever & always #secondact #shesgettingmarried #mybabygirl #awedding #mollyandjoel."
Molly's engagement is right on the heels of her brother, Zach Roloff, announcing he and his wife Tori are expecting their first child together. The baby will be Amy and Matt's first grandchild.