Stephanie Castillo, 36, was charged with six counts of murder and manslaughter for the November 9, 2020, slaying of her newborn twin babies.

A monstrous Bronx mom killed her twin newborns in 2020 and dumped them like garbage in a rat-infested alley — but was only just nailed for the heinous crime, law-enforcement sources told The Post.

Police have arrested the mother of twin babies found dead outside a Bronx apartment building nearly five years ago .