Just because I was curious...if she wears a size 15 in men's shoes, then the conversion for that to women's would mean that she wears a 16 1/2 or 17 in women's sizes...

One thing to look at and you may consider this...if she is really tall and doesn't want to wear heels at all for the consideration of her date - many bridal stores carry those ballerina type "slippers" that look really cute and stretch to fit the foot. They can be dyed to match her dress too!

And to be honest, most of those attending proms generally took their shoes off during the dance and after party...yeah - look nice for about an hour and then stocking foot the rest of the night.. lol

I truly wish I could be of more help to you!

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A blessed thing it is for any man or woman to have a friend, one human soul whom we can trust utterly, who knows the best and worst of us, and who loves us in spite of all our faults.