One other thing I thought of: a land line is tied to an address without needing the child to be able to give the address verbally. My oldest can, my youngest is still learning, but I am also assuming all bets are off if they're scared.
Also, I'm sorry for the various typos in the previous post.
FYI, all mobile phone numbers in the US have the option of being tied to an address for 911 purposes. I assume the default is the billing address, but the address can be changed to be specific to each phone number.
Also, I'm sorry for the various typos in the previous post.