Our 5 yo male lemon, George, has suddenly been extremely aggressive to our 6 yo female Beagle, Maddy. He follows her around, growling, like some punk looking to provoke a fight with a smaller classmate. This JUST started today. My wife came home to find Maddy outside (alone) waiting for her. She had a small amout of blood on her face and now a scab between her eyes. George obviously attacked her while we were at work.
Strangely, he has no problem with Molly, 5 1/2 yo Beagle...
He was very aggressive toward our 10 year old Shep mix up until the day we had to put him down due to complete loss of muscle in rear leg. After that (Dec, 2001), the 3 have been like one happy family; they play, groom each other, etc.

WhatEVER caused this new behavior is really devastating to us! PLEASE, if anyone knows anything about this subject, email me and or post here. Any replies would be greatly appreciated.

BTW, George is normally the most gentle creature you ever saw! He's a real 'mama's boy' around my wife though he is skittish around male strangers...