When the kids were younger, we would tell them that they were allowed to stay up all night on New Year's Eve. The very thought was wildly exotic, and terribly audacious....playing fast and loose with bedtimes might alter the space/time continuum beyond all recognition! "Who knew what could happen?" they would squeal in horrified delight. In reality, they very rarely managed to keep their eyes open past 10:45, despite their most gritty determination.
When Thing 1 was about 8 or 9 or so, she came to me at around 10 o'clock on New Year's and said that she was tired and wanted to go to bed, and would I come and tuck her in. (This behaviour wasn't unusual for Thing 1; she was the only 3-year-old I knew who would voluntarily go to bed, by herself, at 7:30. Thing 2 would fight to the death any idea of bedtime, no matter what the time, or the fact that she was so tired she would drift off to sleep in mid-sentance.)Without thinking too hard about it, I said 'of course' and put her to bed.
The next morning, when Thing 1 bounced out of bed, she happily asked if tonight was the night that she got to stay up all night. Oh, dear. I felt so bad for her...she had gotten the whole "Eve/Day" thing completely mixed up, and had gone to bed early the night before so that she would be rested for the coming night. She was so disappointed.....a year away is a long time when you are 9.
She never made that mistake again.