My daughter is only 8, but she is already nostalgic about books that she loved when she was younger. When the Goodnight Train sequel arrived (review to come, it is lovely), she had to read it immediately. She adored it, but I know that love was partly a response to how much she had bonded with the first Goodnight Train book.
A day or so later I got out a bunch of picture books that had been favorites and stacked them on the table for the next day's breakfast reading. (We were taking a break between Harry Potter read-alouds.) She looked through the stack said "Oh, The Curious Garden" in that tone we all use for nostalgia. Like "Oh, something that I have loved and haven't seen or thought of recently. How lovely." I couldn't even get her to eat dinner until she sat down and read it herself.
She's also been quoting from Little Blue Truck recently, for some reason, even though we haven't looked at that one in years. It's not so much the quoting that catches my eye, but her affectionate tone when she does it. Like someone sharing a fond memory.
I think we can build on this nostalgia, actually. I know I have some books that are favorites now in part because I read them and re-read them over the years, constantly reminding myself about my previous love for the book each time. Gone-Away Lake by Elizabeth Enright and The Changeling by Zilpha Keatley Snyder come to mind from middle grade, Listening Valley by D. E. Stevenson from adult reads. So my task with my daughter is going to be to weed through the picture books so that I can keep the ones we LOVED in one place. Then we can reread them regularly, and keep that nostalgia building.
What about you? Are you nostalgic about favorite books? How about your kids?