First comes baby, then comes marriage!

Teen Mom 3 star Mackenzie Douthit is engaged to baby daddy Josh McKee, the MTV reality star announced via Instagram Jan. 7. Sharing a picture of her diamond ring, the 18-year-old wrote, "I said yes!"

Douthit, who got pregnant at age 16, is mom to son Gannon, 15 months. This is the second time the cheerleader and McKee, 19, have been engaged; the high school sweethearts called things off in October 2012.

In the spring of 2012, Douthit spoke to Us Weekly about her dream wedding. "We want like hay bales for people to sit on, and we want it in a barn, and we want to ride up on horses. We're very country people," the former 16 & Pregnant star explained. "We went to prom in camouflage last year. And we took pictures with like guns, holding them. I was four months pregnant, but..."

The future spouses will soon relocate to San Diego, Calif., where McKee's Marine Corps base is stationed.

This article originally appeared on Usmagazine.com: Mackenzie Douthit, Teen Mom 3 Star, Is Engaged to Josh McKee -- See Her Ring!