Ugh, I hate that. We've got a stray my wife lets come in when the weather is bad and the damned cat sprays every time. Hopefully fixing them will take care of yours doing it. :)
thank you i never thought about that. they ain't fixed yet, he said he was going to do it over a month ago and still hasn't. which makes for a real pleasent smell when you walk in the door, since they both spray everything.
Hmmm... i'd suggest getting them fixed if they aren't.
If they are...sometimes you get what's called "Residual sexual behavior". There's just enough testosterone to give kitty "urges".
Regardless, if a male goes outside and has "relations" with a female in heat, they'll carry the scent back with them. The male who's a shut in and probably doesn't remember what a female cat looks like...well, it gets a little confused by the scent of a female in heat on (in this case, his brother) the returning cat...and can lead to something close to a french farce. :)