“Ahhhhhhhh,” Posey moans as he cools his hot feet in the sea. “Why is the beach made of hot, squeaky dirt?”

I laugh and pick up a fistful of sand. “This is not dirt,” I tell him. “It’s sand. And you’re going to love it.”

“I doubt that,” Posey complains as he steps carefully out of the ocean.

“Suit yourself,” I say, picking a spot near the water to spread out my towel and set up my chair. My parents can see me, but Posey and I can also still be private.

I plunk onto my chair, slip on my heart-shaped movie-star glasses, and put on my sparkly strawberry-scented sunscreen. Posey lies down on his own invisible towel beside me.

“What do you think of the beach?” I ask.

Posey rolls over and props himself up on one elbow. “Well, I like the sound of the waves, and the wind feels nice—but what do people do here? I’m bored.”

So much for relaxing, I think. But that’s okay. I can’t wait to show Posey how much fun it is at the beach.

“We can do you whatever you want to do,” I say.

Posey pulls a shovel out of my bag and smiles. “I want to build a sandcastle!”