They are both boys, and whte 14 year old moved in with us as a stray, but we have had the 2 year old from kittenhood. The younger cat goes out, where as the older boy is indoors 95% of the time. When the younger one comes in, the bigger one licks him, similar to how his mother would. But after about 5 minutes, they fight, wuite aggressively. The bigger cat lies on the floor, attacking to younger one from there, wheras the younger one jumps all over him, they make an awful sound, then, as suddenly as they started, the stop and the little one strolls off... WHY ? they are both spayed. I worry the older one will get hurt, as he is not as active or nimble as the 2 year old.