I'm sorry to hear about this, and I must say your mom seems a little bit anxious to jump the gun, sorry if that comes off wrong.
As for the food aggression, how are the dog's fed? Are they fed together or seperate? or do they free feed?
If they are feed together or free feed, than my suggestion is to feed them in seperate bowls in seperate rooms. How many other dog's are in the household (you mentioned a few more I think), if the only one that is doing this is the small one, I would single the little one out for a short period. Feed all the other dogs together than feed the little one last and alone. Another idea and I only mention this because it was brought to our attention for our 2 foster brother's and it did work, is to feed the other dog's and basically sit the little one near by so he can see the other's eating but NOT letting him near the other's, teach him to "sit" if he doesn't already know, and hold his collar or put a leash on him, and make him sit and watch and when they are done eating than feed the little one. I think the idea behind that is let the little dog know who is in charge
I don't know really, we tried it because we were out of ideas and it worked and now they all get fed together except Ajax who still has to be fed alone, but his food aggression as decreased quite a bit.
As for his aggression towards your dog and people, I would call around to area vet's and find out who they would reccommend for training, it sounds like the little guy not only needs obedience training, but he needs to be evaluated by an expert to help determine why he is doing what he is doing.
Don't give up just yet, there is always hope
hang in there hun.