Looking for a book where childhood friends reunite

Ideally a mystery or thriller novel, but open to other genres. I’ve been watching Yellowjackets and the plot is split between what happened to the characters as children and the older cast twenty years later. I’m not 100% sold on the series, but I’m interested in the dynamic of characters who knew one another as children coming together as adults and seeing how one another have changed and stayed the same. No romance novels please.

by OwnerofNeuroticDogs