What does Lydia's necklace symbolize in the novel, American Dirt?

The three loops on Lydia's necklace serve as symbols of family and deep abiding love. Each of the loops on Lydia's necklace represents one of her immediate family members. Sebastian gave Lydia the necklace when Luca was born, and when she is nervous she has a "habit of looping the three interlocking circles together onto the tip of her pinky nail" (20). These loops and rings comfort and strengthen Lydia and represent the circle of familial love and motherhood. They remind her to honor Sebastian's death and protect Luca at all costs.