I have an orange tabby cat who used to be feral--well, still is, somewhat. When it was about six months old, I trapped it and, with the help of a local feral cat assistance group, had it neutered/spayed. I wasn't entirely sure what sex it was, but when my group contact came to pick up the cat, it hissed and spat at us so ferociously, I assumed it was male (sexist that I am) and named him Leo.
When "he" came back from the vet, though, "he" had a shaved belly--which you'd only do with a female cat. I assumed the vet who spayed the cat knew better than I what sex it was and changed the cat's name to Leona.
Over time, this little feral cat became very friendly with me and, eventually, I invited her into my home. She's about two years old now and has been with me for almost a year.
Now, about a week ago, she started peeing standing up--very rude! I was hacked at her until my boss (who has two cats) said Leona might be doing that because she has a bladder infection. So I made an appointment with the vet (reluctantly--it was so not in the budget).
Well, it turns out that Leona does not have a bladder infection--LEO was spraying! My vet says "It's a boy!"
Now, one might think gender would be obvious on a creature who doesn't cover up its goodies with clothing, but not necessarily. I once had a cat named Willy on whom it was completely obvious that he was male whenever he rolled over to lick his intimates. But I never saw that on Leo. Guess he's too fuzzy there.
I rearranged Leo's favorite litterbox to hide it from the ferals who come by to graze at the feeding station outside the sliding glass doors in back of the house (I feed and TNR feral cats and maintain a sort of roving colony of them in my back yard), in case seeing the ferals was stressing him out and causing him to spray. I also tacked up a garbage bag around the back of the litterbox in case of future "misfires"--and it's a good thing, because he did it again this morning. And my vet gave me some "happy pills" to try on Leo, good for anxiety. Leo's always been a mite paranoid, so I do hope the pills help cool his jets.
I'm not nuts about having a male in the house, especially one who sprays (I thought I had two girls--I'll introduce Minnie later). So far, Leo confines his misdeeds to his tall litterbox with the plastic backdrop, but I sure hope he stops spraying altogether after a while. Maybe the pills will help. If they don't, I don't know what I'm going to do, since he's still semi-feral and can't be adopted out to anyone else.
Above is a photo of Leo. He looks so dignified, doesn't he? HA! He's an affectionate, rub-on-everything, kittenish little thing--he only looks sober in photographs!