The presumption in Florida is for time sharing with the parents, that both parents should have joint custody and decision making regardless of how the time is split up. If you want to change that, you basically have to show that the other parent is unfit, or dangerous to the child, or needs to be supervised for some reason. The courts don't consider that a child should be just with mom simply because the child is younger, unless mom can show that dad can't care for the child.
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