i believe it's not good to hurt sentiments of yr own kids by letting other kids share or borrow their stuff , it's ok for sometime or for some of the stuff , but not for things which r dear / favorite to yr own kids , and others should respect that too.
i know of one mother who whenever someone gave her kids gifts or toys or eidee or whatever, she would take it and give it to someone else. i know another aunty who did that with her kid's eidee