This happened in the ’90s when my daughter was 16. She went on a road trip with her dad’s new family. On the 5th day, I got a postcard from her saying they’d be staying an extra 2 days. When she got back, she apologized for not telling me.

I said, “But you did! I got your postcard!” She lost all color in her face and said, “We didn’t send anything. We decided not to because it would’ve taken more than 2 days to reach you anyway.” I was so confused.
I went to grab the postcard from my closet, but I couldn’t find it. I was 100% sure I’d placed it in my pink box where I keep all my postcards, but that one wasn’t there. After all these years, I still get goosebumps whenever I think about it. I’m certain I saw the postcard and her handwriting—I can even remember the details on the card very clearly.