I would bring her in to have her try on the gloves and see which one fits her best. Here is a link though to give you an idea on prices for Youth Gloves.
I agree. I never understood how anyone could order a glove from a catalog or online. You've got to have it on your hand and see how it feels. That being said, glove size is the first factor you want to take into consideration. Depending on how big the 8-year old's hand is, that will decide the most important part. Make sure it is big enough to fit the size softball she is using comfortably and still maintain a secure fit to her hand.
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