Their Relationship
It’s not really surprising to hear and know that Kyle doesn’t act the way he did to his former partner to other people he’s with. That’s understandable given that he’s used to having his buddy next to him most of the time and speech so much time together solving crimes.
Parting Ways
When Kyle’s time on the force ended, John wanted to keep him, but he could not take care of him when he was on duty. He wanted to do what was best for that dog, so he let the Smiths adopt him. However, Officer John certainly felt sad to be away with his partner.