We just brought a 13 week old EB male puppy into the house with our neutered five year old male and there's been no peace since. Spike, the old guy absolutely hates this pup and has attacked him several times. Once resulting in injuries requiring a trip to the vet. Fortunately nothing serious. Spike was raised with an adult female and they fought on occasion when he was around two but it eventually passed and they stopped. We've had other puppies in the house and he gets along well. I don't understand what it is about this one. He sulks around the house. Sits in the corner and won't come when called and looks for any opportunity to go after the pup. Any suggestions? We really like both dogs but don't want to deal with this for the next few years.