At the end of the day it's your choice but just put it this way... yes it will be a financial drain on you but you will learn to love this puppy. Your kids think they love this puppy at this moment although they would soon learn to love another puppy so if you keep the puppy you release that breeder of her duties.. If return the puppy and you rub her nose in the fact that she sent an unhealthy puppy out into the world and maybe she'll think twice about doing it again.