[Madara Uchiha]

My Yorkshire Terrier, named Shade, is going on 2 years come January. He was a very good puppy when we first got him, at about 5 weeks of age [a little early?]. I wanted him to be completely opposite of my outside dogs, Blossom and Dexter, for we feed them human food with their dog food sometimes [they're medium sized]. So I told my parents not to give Shade human food, because I didn't want him to get possessive. My parents assured me that he wouldn't because Blossom and Dexter weren't possessive. I raised Blossom and Dexter from birth so I taught them not to be possessive. But I made them promise not to give Shade human food.

Turns out that they'd been sneaking him human food, when I'm not looking. They'd toss him a piece of chicken or something. So now he growls whenever he steals something, he runs away when he knows that he has something that he shouldn't. He even snaps at me if I try and take away something that's potentially dangerous to him. He got ahold of my brother's m&m candy and I'd nearly had my hand covered in scars after successfully taking all candy pieces out of his mouth without him swallowing.

My parents get mad at Shade when he bites them but I keep telling them that it's because they exposed him to human food, when I particularly stress the yorkie on not getting into it. My parents just don't seem to get it; my dad will come into my room and say, "Shade says he wants a snack." I'd say, "He just ate dinner. He doesn't need a snack." Then he'd continue, "Just give him a snack." Then he'd get angry at me if I don't want to give him anything. I don't want a fat terrier.

However! I decided to continue with Shade's training [I don't know why I stopped] to keep him occupied. He knows how to "Sit", "Beg", "Twirl", and "Down". But the thing that I've been stressing most is "Leave It". I'd toss a snack onto the ground and tell him firmly to "Leave It" and he'd stare at the snack but not eat it. Then when I pick it up and say, "Good Boy", I let him eat it. I trained him like this for a week. Yesterday it was put to the test when he got ahold of a potato chip. I saw him eating it and I told him to "Leave It" and he literally dropped all of the pieces out of his mouth and stared at them.

I'm so glad that it's working! But I fear that it'd stop working if my parents keep secretly feeding him. How do I get them to respect my rules as a dog owner? And how do I keep his training from possibly diminishing because of them?