Parents often do these sorts of things mindlessly or because they feel a child is outgrowing that stage of their life - either way it affected you to the point where it's still in your thoughts today.

Should you get another bunny? It's interesting isn't it? I mean it wouldn't replace the one you lost, you've found that out yourself with a another stuffed toy someone gave you.

Perhaps there is a part of you who's concerned about some aspect of your future and this is a way of trying to feel more secure? What is it about the toy that would mean so much to you now?

Perhaps psychotherapy would be helpful in dealing with these sorts of memories - do you have someone in mind? Good luck.