question:  Why did Judy spent a week with her grandmother for a week during summer?
context: Maybe you were mistaken about a thing or two before the flood, but what about the haunted house you moved into? You were the one who tracked down the ghosts in the attic and the cellar and goodness knows where all. There was one I used to call the spirit of the fountain, but what she was or how she spoke to me is more than I know. It all began, she finally told them, the summer before they met. And so it was that he spent the summer Judy was remembering in Farringdon where the Farringdon-Petts had their turreted mansion, while she had to suffer the heat and loneliness of Dry Brook Hollow. Her thoughts were what had made it so hard, she confessed now as she reviewed everything that had happened. Your grandmother never throws anything away. She had seen her father’s tired eyes and had realized that a busy doctor needed a vacation much more than a schoolgirl who had too little to do. He and Judy’s mother usually went to the beach hotel where they had honeymooned. Every summer Dr. Bolton and his wife relived it. And every summer Judy went to stay with her grandmother Smeed, who scolded and fussed and tried to pretend she wasn’t glad to have her. In another year she would have outgrown her childish resentment of her parents’ vacation or be grown up enough to ask them to let her have a vacation of her own. In another year she would be summering among the beautiful Thousand Islands and solving a mystery to be known as the Ghost Parade . As Judy wiped it away she noticed that it had fallen on a picture of a fountain. The thrill of walking up to the door of the palatial Farringdon-Pett mansion was still ahead of her. On the lawn a fountain still caught and held rainbows like those she was to see on her honeymoon at Niagara Falls. She and Lorraine had listened to this much of what Judy was telling them without interruption. I wasn’t thinking of anybody but me, Judy Bolton, and what I wanted.
output:  So that her parents could take a vacation.
options:  So that her parents could take a vacation.  So that her grandmother would have an opportunity to spent time with her.  So that her father, a doctor, could travel out of the country for work.  So that she could solve mysteries that were filed away in her grandmother's attic.