Hi My Name Is Cindi I Have A 4 Year

hi my name is cindi I have a 4 year old granddaughter that bearly gets 5 hours of sleep a night and she is so crabby all the time. she has had a rough life living with her mother. my son has part custody of her and we r trying to find out why she is doing this. she should be sleeping through the night. we have seen dr.s and they say give her Benadryl or melatonin! this isn't working so we called the dr. and he said we can give her as much melatonin cause it wont harm her. isn't there a different route to get her to sleep.
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