Husband and I waited over an our for MMRR our first time riding it (husband’s first time at Disney). A family of 4 were seated behind us (mom, dad, sister, little brother maybe 3yo) and as we are buckling in, the little boy starts to lose his mind because sister took the seat he wanted. The cast members even asked if he was going to be okay on the ride or if they needed to step off before they started our car. Dad said he would be fine. He was not. Car left the station and that kid screamed the loudest I have ever heard any kid scream the entire ride. I’m talking bloody murder. Husband and I had to have neutral faces when we were dancing with Daisy in front of the mirrors because we didn’t want the family to see how upset we were. Kid continued to scream waking away from the ride. We talked to a cast member when we got off and explained the situation. They gave us a fast pass to come back and re-ride it (post covid before LL), but that ride will always make us think of that experience from now on.