Cat peeing on people specifically
 

My friend has a cat who is an outdoor cat. He disappeared and returned a month later. He has a leg injury but he is not peeing on people. Why would he be doing this kind of behavior? And can this be modified?

Has your friend taken him to the vet?

What do you mean by peeing on people, is he spraying them? If he's spraying, he's marking his territory.

Has the cat been neutered?

Cindy

Stressed Cat
 

A stressed cat. Any changes in the household? Stresses such as arguing (more than usual)? Moved the furniture around? Strangers visiting (friends or even the repair person)?

Cats do not like change.

If he is not neutered she should run, not walk, to the nearest vet and get him done, check him for a urinary infection and have the leg seen to as well; if he was in a fight there is a risk of infection.
The health issues one would notice in an indoor cat (litterbox problems, wounds, changes in behaviour indicating pain or fever) all go by the board when a cat lives outside exclusively. If she is attached to him, she should work on keeping him inside for at least part of the time. A cat left outside 24/7 pretty soon becomes a semi-feral, badly socialized animal (marking inappropriately) who drops by for meals and disappears for days at a time. Not very satisfying and potentially risky.

Vet!!!! Asap