Nina Stibbe’s “Reasons to Be Cheerful” is so dense with amusing detail that I thought about holding the book upside down to see if any extra funny bits might spill from the creases between the page.

There are the rich and there are the very rich, and while the very rich exhibit varied demographic characteristics, the family at the center of Jenny Jackson’s sparkling debut novel, “Pineapple Street,” is of a highly specific sort: the pedigreed, never-touch-the-trust-fund-principal, tennis-playing, old-money-Brooklyn WASP.

The assignment: Craft a novel from the literary equivalent of found objects. Consider the narrative possibilities contained not just in letters and e-mails, but in school report cards, emergency room bills and police reports filed by night managers at Westin Hotels.