There are a great many themes within the novel and a major one is grief. Grief comes in many forms, none of them are right or wrong. Everyone grieves in different ways. Lukas and Rebecca are still coming to terms with the loss of their factory owning father (book one). Lilly Yoder is recovering from the sudden death of her parents. The town is still feeling the effects of the loss of the men in the factory fire (book one). Everyone needs support and in a small close knit community, they all try to help each other.
Families are another major theme. Family members stick together. They help each other. The extended Amish community seems particularly good at supporting and loving its members.