A rambling lakehouse, a gaggle of cousins, and one very patient grandfather makes the summer Sirena learns to swim something special. Sirena spends part of every summer in a rambling lakehouse filled with cousins, aunts and uncles, and her beloved Poppo (her grandfather). But despite how inviting the water looks, Sirena hates swimming. Until Poppo's gentle words and example tempt Sirena into the water to discover the joys of swimming--until she's a veritable mermaid. As their lakeside vacation ends, Sirena discovers that her present is tied more closely to Poppo's past that she imagined. This is a tender story about the power of intergenerational relationships and overcoming your fears.