text: how can a child fake a seizure? shaking all over, head side to side rapidly, foaming at the mouth based on the age of the child i dont think some can.. i have seen older kids do it as a joke and use a alka-seltser as the foam...some did it wit dish soap.. if you think a child is faking it smell the foam .. it shouldent smell like soap.. or candy .. it should smell like spit..