What is an example of symbolism in the novel, The Two-Family House?

The house on Christopher Street symbolizes a tight-knit family that depends on each other. However, some characters – specifically Mort – see the house as confining. After Rose and Helen switch the babies, Rose comes to hate the house and the enforced closeness. For Helen, the house always symbolizes the ability to keep her family together. She admits at one point that she would never have agreed to switch the babies if she had not expected that they would always live under one roof so that both she and Rose would always be there for both Teddy and Natalie.