This was at a ballet school performance. It was for kids ranging from 5 to 16 year olds.
For one of the younger age groups they did this thing where one kid pranced from one corner of the stage to the other, and then another kid would do the opposite, in a big X pattern. And they would have these gigantic shit-eating grins on their faces. Just horribly precious.
Well I started losing it at about the 15th kid but it went on for like 40 children! By the end I was in tears and all the other adults in the audience near me had found it contagious so everyone was just sitting there laughing at their own children.