The Yellow Yacht

"Y is for "YACHT . . . Dink, Josh, and Ruth Rose love visiting their friend Sammi, the prince of Costra. They swim, soak in the sun, and admire the bright yellow yacht that is moored just offshore. But the owners of the yacht are acting a little suspicious. And there's suddenly been a robbery on the island. Can Dink, Josh, and Ruth Rose find out a connection between the robbery and the mysterious yellow yacht?