M rounded up a special co-star edition of one of our favorite games: guess which celeb is older! If you think you know which star was born first, put your celeb knowledge to the ultimate test.
Jason Dolley plays Bridgit Mendler's older brother on Good Luck Charlie, but is he actually older IRL? Ross Lynch and Calum Worthy are BFFs on Austin & Ally, but in reality, are they the same age?
Play the guessing game by clicking through the gallery. Tell us how many you got right in the comments!