I will try to make this long story short. Brutus is 2 years old and I have a 14 year old mutt, my kids are 14 yo boy, 9 yo & 8 yo girls. Brutus was always a happy go lucky type guy until late June. One night when my 9 yo daughter was locking him in his create he snapped at her. He didn't growl, just snapped. We worked on the pack order and did a lot of obedience training. Brutus hasn't snapped at anyone since, but he growls at my 8 yo sometimes other times he is great with her.
I took him to the vet when this started to make sure that there wasn't anything physically wrong with him. The vet told me that his behavior looked like he had be abused. I have had him since he was 6 weeks old and no one has caused him harm. But he was tucking his tail, lowering his head and hiding behind my legs when the vet walked towards him or reached for him.
He seems to have a food aggression that makes me very nervous. During feeding time, I set the bowl down, tell him to watch me and then tell him its OK. He eats his food in about 30 seconds. I have tried to take his bowl during a feeding and he lowers his chest over it and growls. When he is finished, I take the empty bowl until the next time.
My concerns are why does he growl at my smallest child and why is he so protective of his food? When we call him to us, he lowers his head, tucks his tail and walks very slowly to us. We give him lots of attention and love, but he acts like everytime we say his name that he is afraid we are going to beat him or something. (****we do NOT hit the dogs at all***)
Any ideas on how to help him get past this behavior?
Thanks

I'm just guessing here, but I'm thinking the dog is trying to reconfigure his place in the pack-- perhaps trying to gain a position above your youngest child, but is unsure of whether or not he can pull it off. If this is the case, I would suggest helping your daughter take a more active role in the care and leadership (under your watchful and protective eye, of course) of Brutus-- see that she is the one to feed him (do make sure you are supervising, given that Brutus is showing some food aggression), have her accompany you on walks, let her hold the leash, or, if she is not strong enough, make sure she walks ahead of the dog, always. Make sure she gets some practice time doing obedience every day with Brutus, and some grooming responsibilities would be good too.

Our case is very subtle, so subtle an outsider wouldn't notice, but as my two boys are approaching manhood (I have a 15 yo and a 12 yo), our very submissive and sweet natured dog has also experienced a period of reaffirming her place at the bottom of the pack. As the oldest boy began to fill out and grow stronger, he made a point of physically picking up the dog and carrying her around (I think it's a boy thing). She at first resisted, but has now submitted to him completely. The younger boy is still scrawny and little boyish, so there are areas in which our dog seems unsure of in regard to pack leadership. The younger boy has complete responsibility for brushing her everyday, though, and that helps. He has complete access to all of her body parts-- belly and hindquarters included. As he fills out and gets stronger, his place in the pack will become unquestionable.

[wishbone]

A lot of dogs that so sweet and gentle and suddenly getting aggressive or acting weird. Observe him closer for some more changes. Most cause of this case is due to health issue, i recommend to seek another vet advice.

Sometimes there are animals behavior that are weird,too many theory.I guess there are things or reasons we cant explain about an animal condition.

Have you considered neutering him. This might help curb the aggression. What other people posted here makes sense also. He might be trying to be a pack leader over your youngster.