Many people fear having their pants falling down while they are doing something important - which is exactly what happened to the person in the above photo. He was walking his daughter down the aisle when his pants fell down. The funny thing here is that the daughter seems to be exploding with laughter, which probably made things even worse for her poor father.
Sometimes, laughter is an instinct that people can't control - like in the case of the above photo. The girl probably felt extremely bad when she saw the photo, but what else could she do? Laughter is one of the best tension relievers, which is why doctors have known for a long time that happy people live longer and feel less stress and anxiety during their day-to-day lives.