It all went down when they were shooting their recent Vogue cover shoot. They both grace the mag's March issue together, and in it, talked about baking and road tripping. Somehow during all of that, the girls decided to throw down an old fashioned game of who-is-the-tougher-friend?
Proving their strength isn't the only contests the two besties competed against each other at. They also did a staring contest, talking contest, and drawing one, totally making us want to be friends with them even more.
See if Karlie or Taylor ends up being the big winner in the clip below. Cutest BFFs ever?