My three year old step son keeps saying things like he doesn't want his mom to die or the dog to die and that it's his job to fight off all the criminals. Both his mom and I don't believe in heaven and want to just tell the kids the truth about things but it's hard to be honest with the fact that everyone dies and that we don't truly know what happens after death and be reassuring that his mom isn't going to die anytime soon.

His grandfather did pass away recently so I see where he's coming from with the death questions but I would appreciate any advice on getting off the topic or answering it easier or anything.

I have no idea where his fixation with criminals being something he has to worry about so if anyone else has dealt with this please do tell.