Your kids do get up earlier than most kids 6:30am is pretty early. My girls 4 and 6 are in bed by 8:00 and up at 7:00. My son is 8 and gets to stay up until 8:30.
Two of my kids are early risers and will get up about 7:00 no matter when they go to sleep. My other daughter would sleep in until 8 or later if she could. So how much sleep a child needs really depends on the child.
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