the longest story short: their dad has never met a woman he hasn't wanted to marry, his five ex-wives will attest to this. but he's from NYC real estate old money and actually puts in the effort to keep every single member of the family so no one says shit. there's ten kids total five being paternal half siblings, 4 step-siblings from marriage 2 & 3, and the lone stepsister from dre's mother's second marriage. dre is currently in the dicaprio era of his life dating girls way younger than he should be, so he really needs someone around to give him the maximum amount of grief over it. her being the youngest in the family madness is just icing on the cake.