Rocky opens with Willa's theory that four-leaf clovers are a symptom of luck rather than its cause, a meditation on privilege and noticing what is already there. On the way back from their last beach day, the family stops for ice cream, and Rocky resists the urge to mourn the vacation prematurely, marveling instead at how grown and beautiful her adult children Willa and Jamie are.

At the ice cream stand, the family's distinct personalities surface in their orders: Willa and Nick debate the chocolatiest chocolate, Rocky sticks with vanilla soft-serve, Maya picks cotton candy, and Jamie chooses black raspberry. They sit at a picnic table and share their favorite moments of the week, citing lobster, mini-golf, family, beach stones, the engagement, hermit crabs, night swimming, and Rocky's mother's pharmacist Regina—an anecdote that had sent Willa and Jamie into uncontrollable laughter.

Willa teases Rocky about once baking a lemon cake in a disposable pan that had briefly held cat litter, and the kids dissolve into laughter together. Rocky reflects on Daedalus, the Pietà, Sandy Hook, and the countless ways parents can lose their children, acknowledging she has imagined many of those losses.

No one asks Rocky her favorite part of the week, but she silently answers: the fact of them all being together and alive. She concludes that grief and love are intertwined and that preemptive loss does not protect against real loss, so the only choice is to love recklessly. When Nick suggests packing, Willa proposes going to the pond instead, and the family chooses one more shared moment before time runs out.