Real sorry to hear about your puppy, Greenport. Is there any hope y'all could take him to the vet before returning him to the pound and consult with the vet about his destructive chewing behavior? Lots of dogs go through long, potentially destructive oral phases. Labs are famous for that, too. But with proper crating, plenty of interaction and chew toys, and sometimes also with some sort of different behavioral training, they can be directed in other ways. Sounds like he's a good pet otherwise. I hate for your mom to be so hasty about returning a pet you're very fond of.