For years, Rosie, a mom of two in Westchester, genuinely believed she had found her “unicorn family” — people with whom she, her husband, and their two daughters were ultracompatible. They had met Dan and Katerina in a parenting class in 2015, back when they all lived in Brooklyn. Their kids were the same ages and genders. The husbands played soccer and texted Wordle scores to one another daily; the women swapped Instant Pot recipes, dragged their kids on weekend hikes to Bear Mountain, and later, when they all found themselves new to the suburbs, helped each other unpack and adjust. Over the course of their decade-long friendship, they had developed a routine of near-weekly sleepovers for their four girls.
It all worked seamlessly because they were aligned on the big parenting deci