Lots of McQueens on Hollyoaks. When they leave/get imprisoned or more likely get killed off (since they are far more likely to be a homicide victim than die of natural causes), there are siblings and cousins (first cousins, first cousins once removed, first cousins twice removed, second cousins, second cousins once removed, third cousins) and their direct descendants coming in to stay in the house and perhaps have sex with each other and each other’s partners. Or with their partner’s parent. Or sleep with Warren Fox, who beat Bart McQueen to death and later found out he had murdered the wrong person. And Cameron Campbell bumped off his wife’s parents before their last grandchild was born. Cameron murdered his brother, Lockie, before their first cousin Courtney arrived and before evil Grannie Campbell arrived.
Serial killer Nico Blake murdered her grandfather (father of both of her parents) before her half-siblings and her own daughter were born. And her half-uncle had previously drowned his mother in the bath. Nico was killed by her mother without meeting her half-sister, who had been kidnapped by multiple murderer Warren Fox. And Warren’s sister Katy died from a drugs overdose from her nephew before Warren’s two youngest babies were born, both of whom he has kidnapped. And some Savage and Blake family members are yet to meet each other.
Grace Black also made her first appearance after her sister, Clare Devine, died. Grace’s three half-brothers weren’t around when Clare was.
Evil Mac Nightingale had sex with his son Nathan’s fiancée, which caused Nathan to fall out of a window and die before Nathan’s nephew Romeo (half-sister named Juliet) debuted.