In the novel The Mirror Crack'd from Side to Side, Lily Price is a young woman who is considering buying a house in The Development in St. Mary Mead. At the beginning of the novel, Miss Marple sees Lily and a young man, Harry, at the first floor window of a nearly completed house in Carrisbrook Close.
Lily says that this house has a nice position, and has two more rooms than another house they had looked at. Harry replies that the other house was just as good, and that one had to pay more for a house that has more rooms.
Lily leans out of the window, saying that you can almost see the reservoir from the house. She does not realise that the boards on which she is leaning are just loosely placed on the sill, and nearly falls out of the window. Harry stands motionless behind her. Lily manages to right herself, and asks Harry why he did not get hold of her.
Miss Marple approaches Lily as she is standing alone in the street, and advises her not to marry Harry, as she should be with someone on whom she can rely if she is in danger.
Later in the novel, Cherry Baker says that Lily broke up with Harry. Cherry says that it is no good marrying someone just because a baby is on the way, and that Harry had not truly wanted to marry Lily.