Sometimes, opening the window for a breath of fresh air is not such a good idea after all!
As is the case with Sarah, who in the course of obtaining fresh air from the outside world also happened to let in a mutant insect (or at least it looks like a mutant).
Without fail, this insect flies straight for Sarah, and bites her on her left forearm. The sing causes an allergic reaction; however, not one that her brother has ever seen before. It is certainly doubtful that any ointment will fix this one.