Probably my copy of the book of The Fox and the Hound, that my parents read to me when I was like toddler age. Honestly it doesn’t have particular sentimental value other than I think it’s cool to still have something from basically when I was born. And it’s a lovely story too.
The runners up are probably my two acoustic guitars that are both in disrepair. And a red and blue flannel shirt that has somehow lasted about two decades and never aged or even lost a button.