My 1.5yr old basenji over the last 4 to 5 months has changed a tremendous amount. I don’t understand what it causing this change. His dog companion past away about three months ago and since he has become aggressive. It’s like I have a different dog. He growls and bites me when I try to pick him up most of the time. He has slowed down and has much less energy then before. I have to beg him to eat in the morning and sometimes at night. We also got a new puppy about a month ago who he plays with and doesn’t seem to have any issues with. Do you think he is just maturing? Or could something be wrong with him? He has seen a vet and she did blood work which came out normal and a fecal sample which also was clear. Does anyone have any ideas or experience with this behavior?