6 week old puppy in danger?

My drunken uncle who lives next door got hold of a 6 week old puppy. He is irresponsible and in no way fit to take care of a dog. I know puppies are supposed to stay with their mother and siblings until they are 8 weeks old and younger puppies require special care, and my uncle shouldn't even have a dog period. I am so afraid for this little puppy. My little sister already loves her so much. What can I do to help this dog? I know my uncle will not listen to reason and return her or give her up to a shelter.