Chocolate is a unique pony, just as his mother is. Having such a serious son was… difficult for her as she didn't know how to talk to him. While the two differ greatly, Pinkie hoped to get her son to show some more pep by giving him some candy. The result was… surprising to say the least.

Basically, sugar paradoxically puts Chocolate to sleep in minutes, much to Pinkie's surprise. The amount of sugar determines how long it takes but it always makes him fall asleep. When he gets older, the effect changes drastically.