What makes Maggie nervous?

Maggie will be nervous for as long as her sister visits.

Maggie will be nervous until after her sister goes: she will stand hopelessly in corners, homely and ashamed of the burn scars down her arms and legs, eying her sister with a mixture of envy and awe. She thinks her sister has held life always in the palm of one hand, that "no" is a word the world never learned to say to her.

No