Heartworms

5 year old girl brought to clinic by grandma because of her chest hurting when she coughs. During the exam, her grandma says "she thought she had heartworms but I told her that only happens in dogs." We both giggle, then the girl says "No granny! I can't have heartworms, I am not a dog! Unless mommy is a dog...or unless daddy is a dog." Grandma says, "Well yes baby, your daddy is a dog, that's for sure!"