Cocker puppy gets aggressive when around food

Question
Our three month old cocker spaniel is normally very agreeable and happy.  However, if food is introduced into his environment (even if people are eating around him), he starts growling and will bite you if he thinks you're going to take the food away (or get in the way of the food).  He will even do this if I'm cooking in the kitchen and something accidently falls on the floor.  He will immediately become aggressive to my kids (he is also with my husband and I, but mainly only when it pertains to his bowl of food).  He was with his brother before we bought him, and it was clear he was the "alpha male" between these two.  We have tried laying him on his back when he exhibits aggression towards us (e.g. touch him while he is eating, if he's okay with that, try to put our hand in his bowl-then laying him on his back when he growls or bites til he relaxes).  It is clear that he does not think we are above him in the pack.  I want him to be able to eat in the room with my kids around and not have to worry that he will bite them if they get too close to his food.

We have another dog, but she does not try to get his food.  She will growl at him if he tries for hers (but she will let my 1 year old take food from her bowl).  

Answer
Hi Tracie,
You're very wise to handle this now.

If budget allows, I'd get a trainer in.

If not - take the approach that "nothing is free" and the first thing I'd do is start feeding him by hand and make him work for it.

His general training is really key at this point and will reinforce his lack of status in the family.  He's trying you on (and apparently winning)so it's vital this stop NOW.

Does the alpha roll you're doing have an effect?  How much general training have you done?  What commands does he know?
Is an at-home trainer a possibility?

Cockers are extremely dominant dogs and this can accelerate if not dealt with properly.  Do note your other dog IS handling it and doesn't allow that behavior from him :)

He needs to grasp that YOU are in control of his food and he eats when and how YOU decide.  If you sit on the floor with a small amount of food - call him, make him sit (and wait) then say "okay" and give food, you're telling him he has to work for this.

One way to establish humans as alpha is to attach his leash to you (belt loop or whatever) and without any conversation...just carry on.  He goes where you go and he has to pay attention and look to you for clues.

Above all...no yelling or hitting...alpha leaders don't get hysterical and meeting aggression with aggression just puts more aggression in the room.  They simply ARE always in control and when a subordinate acts out, they go very, very still - eyeball the bad boy - and maybe emit a very low warning growl.

Dogs like yours need an "every day in every way" lesson that humans rule.  Never let him go out a door in front of you.  Do not let him (for now) on the furniture or your bed.
Make him work for his food.  Give him no treats unless he obeys the "sit" command.  Count to five, give treat. If he begs at the dinner table, spritz him in the face with water and say NO (not a "stream" of water - a spray).  Never feed him before you.  He waits...alphas eat first.  He'll understand this.

If he growls, say NO and stare right into his eyes and do not lose eye contact until he breaks it.  (You win)

And remember, dogs like little kids, continue behavior that "works for them" and this is working for him right now.
At some point he may decide to expand this behavior so nip it in the bud now.
Delores