Sounds like shes drinking enough if she was peeing any less on a longer time period i would worry. Also as the baby gets older they start to pee less often and usually more when they do. They get used to holding it during their sleep too all I'm their own. This helps when its time to potty train. If you ever get worried about dehydration try to look for the signs like small cracked lips, constipation, top of the head dips in, gentle pinch of skin will not fall back right away it will stay raised.
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