He has issues with another male we got a year ago, but they just avoid each other usually or just growl at a distance; now he tries to attack him and the other cats. A month ago he accidentally got his bottom tooth knocked out and we wonder if he got head trauma from that as that is when the problems started. His behavior is really weird and changed all around so we are trying to figure out what's wrong. He is fixed and we try to keep him indoors (he just likes to lay in the backyard sometimes). Any help would be great! Thanks!