I found the following rescources online. All of them list an age of 11 minimum and the ages for taking the case are for 11-15 yr olds. I cannot find online an article that was in our local paper. It was simply about a babysitting course for children 11-15 yrs old. One article I read but did not link to because it was from the UK said that it was recommended that any teen younger than 16 take a babysitting course. I also know that my neighbor where we used to live was not allowed to have anyone younger than 12 stay with her daughter. She was divorced and those were the regulations of their situation. I believe the issue had come up since he'd left the 10 yr old alone at his home. When she found out she had a conniption fit and called her lawyer who looked up the laws. You should perhaps check with a lawyer depending on how serious you want to get. They might be able to just quickly tell you if it could be an issue.
http://www.redcross.org/services/hss...babyindex.html
http://www.medem.com/medlb/article_d...FC&sub_cat=106
http://www.aap.org/family/sitting.htm
Personally this is an issue near and dear to my heart. I'm a day care provider and former teacher. I've seen too many kids left unattended or in inadequate care and bad things come of it. If anything had happened to your 4 yr old you can be sure that the 12 yr old would not have been held responsible. Your wife would have been the one held responsible. That might be something to think about.
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