Read the excerpt and answer the question below.
The Open Window (abridged from the original by Saki)
"My aunt will be down presently, Mr. Nuttel," said a very self-possessed young lady of fifteen; "in the meantime you must try and put up with me."
Framton Nuttel tried to say something flattering to the girl as he waited for the aunt, Mrs Sappleton, who was to come. He wondered if visiting these strangers was really going to help cure his nerves, and if this treatment would work.
"Do you know many of the people around here?" asked the niece.
"Hardly a soul," said Framton. "My sister was staying here, at the rectory, some four years ago, and she gave me letters of introduction to some of the people here.”
"Then you know practically nothing about my aunt?" pursued the self-possessed young lady.
How did Mr Nuttel know the Sappleton family?