I adopted a male German Shepard and his name is bullet about a year ago and he is currently about 2 years old now. My brother ended up moving in with me and he owns a male German Shepard name Harvey. They both came from the same parents and are brothers about the same age but they cannot be within 10 feet of each other without trying to fight to the death. We don’t want to neuter them unless we absolutely have to. Is there any hope of them getting along?