During that period, Harry returned to Privet Drive to stay for another week, given the so-called "blood protection."
It was not until a week before the start of term that Hogwarts students began buying their new textbooks.
The diary had been lost all summer without a trace, and Alistair suspected that during this week of buying books, someone might deliberately slip the diary among the textbooks so that the students would bring it into Hogwarts.
Chapter 102