possesive golden

Question
I have a 15 month old golden retriever, Oliver. He is an all around well
behaved well mannered dog. In the last 2 months, however, he has developed
one very bad behavioral trait. he has begun to be very possesive of his toys/
sticks/balls, to the point that he has begun to fight when he believes another
dog is after his toy. The part that confuses me most is that I also have a 5
year old black lab, and Oliver would NEVER fight with her. I'm guessing it's
because she is the more dominant of the two, but she certianly doesn't act as
such.

Answer
Sounds like the Golden thinks it is pack leader. You didn't mention if it is neutered and has obedience training. If you read my post on the Jack Russel siblings it details pack leader roles and the importance of obedience training and the nothing for free program. Don't let toys lay about. Confiscate them all. The dog only gets one toy at a time and only after it has performed some task (sit, down, whatever you choose). Likewise it has to perform for food, water, affection, etc. You need to be the pack leader. Any dog that won't let me take anything away gets a lemon juice squirt. No one should tolerate bad behavior from their dog.

regards,
Henry Ruhwiedel