This is the type of (urban) survival that I am interested in. Last year, several friends and family members made telephone lists. The numbers include home phone, cell phone and work phones. The list also includes other family members and/or numbers for a close friend or two. The phone numbers involve people in four different states. 
I made a list of all the numbers and have sent them to each individual on that list. This may seem like overkill, but there many be times that local calls might not get through, but long distance calls  might work. This has created a web of numbers for cross referencing among us.
Your children should have a list of these numbers in their backpacks for school. If they get completely separated, it might be of help to someone who is helping them.
    
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