How long after his mother's death did it take Peter to have a day where he did not think of her all day?

It took a year and 16 days for Peter to have a day go by without thinking about his mother. On that day he went with a friend's family on a camping trip. They had canoed, fished, swam, pitched tents, and grilled hot dogs. Peter was so busy that he did not think of his mother the entire day.