My then-young nephew was disturbed by the death of my mother (his granny). He wasn't there at the time but was upset for a long while by the concept of death, was afraid of going to sleep - and not waking up. Young children do not cope with it well. Older children, teenagers, can learn to cope philosophically, as adults have to. And unfortunate as it is, it is an inevitable life experience that needs to be learnt.
Keep nippers under 10yo away. Handle the older ones in a sensitive but solemn manner.
There's two kinds of people, those that hear the music and those that don't.