While the secret wedding is obviously a surprise for fans, it's even more shocking because they never even announced that they were engaged.
The couple welcomed their first child together, daughter Emilee, six months ago. This is the second child for each of them, as they both have daughters from previous relationships - Kristina with her ex husband and Gary with ex-girlfriend and fellow Teen Mom star, Amber Portwood.
My lil girls! pic.twitter.com/Qq3sAX42rD— Gary Shirley (@ItsGaryTime) October 31, 2015
Speaking of Amber, she's going to be walking down the aisle soon, too! The 25-year-old is engaged to boyfriend Matt Baier and the pair plan to tie the knot in October of next year.