Tell them about all the bad things that can happen in this world.
Be honest, give examples, take questions.
I did not let my girls go on sleep overs until they were 8.
I felt they were aware enough at that age.
Also you can give them a cell phone to keep in a bag if they need to call you.
Instruct, instruct, instruct.
Kids are smart if you inform them of stuff.
Teach them right and you will sleep well.
You know your kids more than anyone else.
I know how ya feel tho.
Have a great night.