Owning multiple cats is often a tricky situation. Whether you want to adopt two cuties together or plan on introducing a newbie to your "first" resident cat, a variety of frustrating problems may arise, from jealousy to pure territorial conflict. Gender doesn't always make matters any clearer or easier, either.
Two Male Cats Together
"Forcing" a pair of male cats to share the same roof isn't always easy as pie, especially if the little guys aren't neutered. Talk about major dominance issues, from one cat spraying to mark his turf to the other instigating some full-out physical attacks. Although neutering often helps reduce these hormonal behaviors, it isn't always a guarantee, especially if the patterns started long ago. Aggression is always a realistic possibility when it comes to male cats sharing the same space, so don't automatically assume that two boys will work any better than two girls.
Two Female Cats Together
At the other end of the spectrum, two female cats may also pose their own set of specific problems, although not typically physical aggression, thankfully. Adult female cats are usually not too shy about displaying "princess-like" behavior, and the presence of another competitor will only often highlight it. A pair of females might find themselves in perpetual battle with the other over your undivided love and attention -- yikes. When it comes to sharing and harmony, you may want to look into something other than two fluffy divas, unfortunately.
If your goal is for two happy cats that get along and don't cause too much trouble, you do have several options, so don't panic just yet. Perhaps look into adopting a pair of two male kittens that have been together since birth -- littermates that are already bonded! If female cats are more your speed, do the same with them. If you already have a cat and that simply isn't a possibility, in the case of same-gender companions, make sure the new one is significantly younger in age. You also may find some success in adopting two cats of the opposite sex, so don't rule that out. Just make sure to get both of them fixed so you don't end up with an unexpected litter on your hands one day -- uh oh.
At the end of the day, no "yes" or "no" answer is in place for whether two male cats will get along better than two female cats. After all, just like people, all felines are separate individuals with distinct temperaments. You may find that two queens get along famously and are inseparable -- aww. You may observe two tomcats sparring until the cows come home -- even after getting fixed. Whatever gender combination you choose for your home, all you can do is be the most patient, loving and fair owner you can be.