First you should explain to the kids that not all cats & kittens like each other & so to just 'throw' them together w/o having 'met' would probably be a bad idea. With any two cats (or more) about to possibly meet, it's always best to gradually let them meet. You can try two different methods that I know of, first you can go to your neighbor's & just explain that you both have new cats & would like them to meet & get along. You can ask to pet or play w/their cat then go to your cat & let it sniff you & learn of the other cat's scent. You can do this over several days or a week or so then you can do the same w/their cat, the neighbor petting/playing w/yours & bringing home it's scent & try to let them meet gradually by this method. You can also try that in addition to doing this: You didn't say whether your cat is outdoor or both in/out. If only outdoor, since the other cat is both in/out then ask your neighbor if they'd keep their cat in while you bring your cat over to meet their cat. While keeping your cat outside, if it's warm enough, leave their door open or the window shades up & possibly window open if it has a screen so both cats can see each other & 'nose' each other while having a barrier in between. That's the way cats usually 'meet' is they check each other out & nose each other (kinda like when dogs sniff ea others behinds). You can know then if they're going to get along. With the neighbor's cat indoors, it's pretty safe from your cat at that time but if your cat starts exhibiting territorial behaviors then they may not get along at that point & you can always use a water spritz to 'squirt' your cat or the other if one (or both) starts getting territorial & mad, that way they can know that's not acceptable. Now, you also didn't say if both cats have been neutered or spayed? If not then it probably would be a good idea to do that. It not only prevents 'spraying' or marking their territories but prevents unwanted kittens & a lot of times, calms them down to where they're more easy going. If they DO seem to get along then you should be fine. Normally when you bring a new cat into your OWN home w/a first cat then the best way is to keep them separated then switch rooms so they can sense the other's scent & then place them to where they see each other but can't touch then gradually bring them closer like putting one in a kennel or carrier so they can touch noses or get to know each other more personally then switch w/the other in a kennel. Eventually they should be able to get along w/o being separated. Knowing that, it should give you some idea of how to go about it w/your neighbor's cat. Now, another thing that makes a difference is if they're both the same gender. Two females generally won't get along. Two males MIGHT but it usually has the same result unless they grew up w/each other on both males & females then they'd know each other already. Now I have read that if the adult is a female then regardless of gender, if the other is a kitten (young kitten) then they usually act maternal or nurturing towards a kitten & accepting of it b/c they don't feel threatened by it, being young & small but I don't know if that's true & don't know if adult males would be that way w/a kitten. It sounds like it may be true w/the females but haven't had that experience that I recall. I hope these tips help & good luck!
