I think it's just a sex question.
My mother didn't want to explain to my little sister about our neighbors (they're gay) because she felt like she wasn't ready to learn about sex yet, so she told them they were room mates. Eventually, when she started using "gay" as a slur (all her friends were doing it, and obviously they have no idea what it means, they simply pick it up from older people) I pulled her aside and explained it to her.
She doesn't use it anymore. Admittedly, it's a hard habit to break for her - for good or for bad, we pick things up from others, and as long as it seems like it's okay we'll do it, especially if we're young and don't know better. I'm not saying it's right, I'm saying that's just the way things are. Eventually she'll probably end up making friends with a lesbian girl or a gay boy, and she'll realize it's hurtful.
We love our neighbors. They're head of our community and throw some rockin' parties. They're just awesome people to be around, to. They're fantastic gardeners. If you get to know them I wouldn't see you ever having a thing against them.