My daughter is sweating a lot at night, when she sleeps. Is this normal?

Maybe. Night sweats can be symptom of something significant or a variation of normal. If this is new, have her see her doctor for a complete blood count a screen for infection.
Maybe. Some kids just sweat more and are more sensitive to heat than others, just like adults. E.G. My middle daughter sweats each night with one sheet on and temp at 64. My other two kids are cold. Just different. There are some medical reasons to sweat more, so talk this over with your doc to be sure everything is alright.