Mary has far too many surnames over the course of these books. It's really very greedy of her.

Anyway, in this one Mary is jealous of her new step father, which is fairly understandable, given that she's only recently been reunited with her mother. Less understandable is her being ashamed of his being a carpenter and lying to all her friends that he's actually a super-rich architect.

It's all very predictable, but nonetheless fun.