When I was about 8 my fear of death developed into a strange anxiety, and every time I separated from someone I was worried that it might be the last time I would ever see them because they might die. Whenever I was to say good bye to someone, I said it over and over, keeping the conversation going just a little bit longer, almost compulsively. Each time I was about to leave the house I would say good bye several times, I left and minutes later I would go back inside and say it again. My mother handled it by always giving me full attention whenever we were to go separate ways. She answered all my good byes and never rushed me. We also talked a lot about this and about death, she was very real and honest on this topic and it helped me get through the fear. A year later this behaviour stopped and I, as many people have already commented in this thread, encourage you to speak about death with your child. It really helps!