Want to LOL? Read ‘Sandwich,’ a new novel about a three-generation family vacation.

I don’t laugh out loud very often when I’m reading books, but I did while I was reading “Sandwich.” And I bet I smiled an average of three times per page.

Catherine Newman’s novel is tons of fun, full of narrator Rocky’s wry observations, like this one, when she sees herself in a mirror while trying on a swimsuit: “There is also some kind of situation between my rib cage and legs — something new that looks like a bag full of dinner rolls, or maybe just a large loaf of peasant bread.”

Rocky, her maybe-a-little-too-perfect husband, their two adult children and, for part of the weeklong vacation, Rocky’s parents have rented a house in Provincetown. It’s something they do every year and that Rocky always looks forward to, although this year has its share of melancholy, in between brisk swims and trips to town to get the good sandwiches.

That’s because, at midlife (and, as the title hints, sandwiched between her parents’ generation and her children’s), Rocky is hyper-aware of the passage of time. She worries about the health of her parents, especially whether they’re telling her everything. She worries about a secret that could drive a wedge between her and her husband. And, watching her children launching their own lives has Rocky feeling misty about previous trips to the same vacation rental, trips when she wasn’t wondering if her son Jamie’s girlfriend is pregnant (she is), but whether solemn little Jamie would ever learn to swim:

“ ‘Daddy’s fine,’ I said. ‘He’s having a lovely time in the water. You’ll join him again out there when you feel like it.’ I was so tired. ‘I will,’ he said thoughtfully. ‘I would like to.’ The following summer I watched from the beach while Jamie bobbed in the waves with his dad.”

I bet parents will relate to the nostalgia of “Sandwich,” which skirts up against sentiment without ever crossing the line because, like Thornton Wilder in the play “Our Town,” Newman is adept at capturing the everyday details of life that seem insignificant at the time but turn out to have shaped us. Wilder fretted that we don’t notice those little moments while we’re experiencing them. But Rocky does notice them and, because she’s sharp and aware that they pass quickly, the beauty of those evanescent moments stings.

Newman’s writing is funny, clear-eyed and compassionate, especially about the foibles of the characters (even, it turns out, that perfect husband). It probably won’t make you want to join Rocky’s family in that vacation rental — there’s only one bathroom and the walls are thin — but it would be fun to share a glass of wine with them and shoot the Atlantic breeze.

Sandwich

By: Catherine Newman.

Publisher: Harper, 229 pages, $26.99.