"Go Maybel, go!" you say with enthusiasm, pumping your fists up and down for emphasis.
Your sister's cries are drowned out by the mare giving a whinny, as if in response. She stamps a hoof and bucks her head up, taking in a good bit of the girl's torso.
Your sister's shorts-clad butt wiggles in panic in front of you. As Maybel reaches the girl's rear reaches the mare's mouth, the horse seems to have trouble getting it in her mouth. The mare eyes you, as if asking for help. Well, you did just encourage the horse, didn't you? As awkward as it may seem to touch your sister there, didn't your sister deserve a good few pushes on her rear after she was so smug earlier?