[Mikey T]

Daisy will attack him out of the blue sometimes. Does anyone have any advice on how to handle this type of aggression? It is usually when Riley comes near her food or if I am on the floor petting Riley and Daisy seems like she gets jealous and she will get aggressive.

Obvious it is not out of the blue if you have secenarios in which you can predict the behavior. First to put a name the the behavior, it is called resource guarding, and as such is a normal adaptive behavior. That said it does not mean such behavior is acceptable. The best resource on dealing with this behavior is Jean Donaldson's book "Mine! a Quide to Resource guarding"
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However if the only time she guard resources is from the other dog then I would suggest other resource than the one above that is more devoted to resource guarding objects form humans even though the same techniques can be adopted for dog v dog guarding.

The resource I would recommend to you is Patricia Mcconnell's FEELING OUTNUMBERED? - HOW TO MANAGE & ENJOY A MULTI-DOG HOUSEHOLD, 2ND EDITION There is a DVD available as well but I have not seen it. For a fair review of the booklet click here

The authors recommend such things as teaching simple obedience exercises to each dog on an individual basis, interrupting overzealous play, controlling doorways, greetings, and mealtimes, teaching dogs to accept being segregated and to accept watching other dogs receive food and attention. The authors underscore the importance of teaching a dog frustration tolerance. All of this is sound and sensible advice. [/url]

The first question is why is rielly allowed near daisy and her food. This can easily be managed. Personnaly I prefer to train the dog to remain at their food dish after eating by at first making staying there more rewarding than moving on by droping food/treats in the bowl when they finish the meal. Over time the number/amount of food dropped can be reduce. Other find it simply easier to feed in seperate rooms, crates etc.

The exercises outline in the booklet mentioned above will hep daisey deal with the fustration of having Riley recieve attention but not her. It also is good for training humans to act appropriately as well. All to often we reward the rude obnoxious dog and hence it become ruder and more obnoxious.

but why is he so interested in it??

It is because that is what dogs do. However contrary to old wive tails dog licking on wounds actually slows healing , it is why we need Elizebethean collar for dog after surgery, FWIW on of Mariah favorite things to do is lick wounds, Her mom is convinced it is because she likes the taste of blood.