Gee.....Never worked with " little girl crushed " grapes. That's really cute. How much juice Mylissa can extract should determine how much wine you can make. If you want to use straight juice, you might be able to do a couple of carboys worth. 100 lb is a LOT of grapes. When I've used fresh grapes, I macerated them in the blender, skins and all. I used 10-12 lb for a 5 gal batch. Added 5 lb of sugar, topped to 5 gal with water, and used a sweet finishing yeast ( Cotes Blanc, just my personal preference). I do a week or two of primary, then rack it off the skins and secondary for a couple of weeks. Be sure your SG is constant for a few days before you bottle. Once had a glass gallon jug explode in my shed. Naaaasty!!!
If you were going with straight juice, you can see how many gallons you get. Maybe do one batch with 5 gal of juice, so much sugar and the yeast of your choice. Do another batch with water added and a different yeast. Fool around with it some.
I'm not a wine expert by any stretch of the imagination. I've only made eight batches of wine to date. Six came out great, two were undrinkable. I started with some questionable fruit ( apples that smelled like potatoes and pears that weren't sweet at all) and ended with shoe polish. You can't make good wine from bad ingredients.
Go for it and have fun. That's really what it's all about.