Sisterlys and normies should never be unpopular. I have 2 sisterlys (Pashmina and Phoebe and 3 normies (Marina, Merengue and Mitzi) on my island, and I love them. Really, I love all my villagers. But then, I have no snooty or cranky villagers, so that might partly be why. There's also all cute in design - except for maybe Pietro, AKA Murderclown.