When DS had just turned 4 he became fixated on the idea of me dying and leaving him. At the time the only way I was able to settle him was to listen, validate what he was saying and be open and honest. It became the time to open the dialogue about life and death. This is something I deal with frequently in my working life so for me it wasn't a difficult subject to broach.
Here is the link to a previous thread dealing with death which you may find helpful.
http://giftedissues.davidsongifted....true/worrying_about_death.html#Post24571
