Here’s the oddest thing I’ve unearthed in a while, what must be one of the first books I ever owned. My guess is that I probably got it around the time I turned five, which also turns out to be about the time the film came out. I remember that the local supermarket in Monticello, Arkansas had a promotion where at check-out kids got a little plastic ring with a little sword in it you cd pull out and put back in and pull out and put back in and so forth.
This book is signed in what is clearly my mother's handwriting (this being before I learned how to read).
The only book I think I’ve had longer is a battered copy of PICKLES THE FIRE CAT. This I loved so much that I kept the library copy checked out more or less permanently. I can still remember how every time it was due we took it down to the library, where I wd check it out again. Eventually my parents got me a copy of my own, which later passed down to my nieces and then later still back to me. It's almost certainly my first book, but not necessarily the one I've had the longest.