When I was a child, I had a particularly loyal friend who accompanied me almost everywhere. I don't remember having grown apart from my friend but there came a time when he no longer went everywhere with me. When I now think of Wormy, it's always fondly.
Did my friend (who is virtually impossible to describe beyond his endless fidelity) move away? Well, he might have had he been a person. You see Wormy (a bizarre name, I know, for a non-worm but very steadfast creature) existed only for me just like Ida's Dotty, who comes alive in a book by Erica S. Perl.