"A little diddy, about Jack and Diane." Maybe the show's creator is a John Cougar Mellencamp fan.
In my imagination, Rainbow's parents were Northern California hippies from the 1970s.
My guess is that Andre and Rainbow didn't want to give their children contemporary "black" names--meaning, names with -sha, La-, Qua-, Tra-, Tre-, etc. And no apostrophes or hyphens. I'm sure they both know the sociological studies showing the bias against black men and women with black-sounding names, and they didn't want to put these burdens on their children. Doesn't make it right (the racial bias, that is). And Andre is very proud of his name, but I'm sure he's had to overcome barriers in the workplace that stemmed solely from him having a black-sounding name.
--I'm not trying to be insensitive, but I've worked in the school system, and I currently work in the medical field. And my black children have young friends with unique names. So when I hear names like Qua-Sim, Za'kir, Zy-nida, Shar-kesha, Na'Shan, Seanyqua, and Tyresha, I want to shake their mothers and ask them what the hell they were thinking when they burdened their kids with these made-up names that are hard to spell and hard to pronounce.