Hello Heather, we have tailors & they can make the costume size as customer requests, so please tell her don't worry about this, just choose 'Custom size' & fill up the body measurements, and we can tailor made for her. n_n
*Custom size costume doesn't charge extra cost, but the processing time will be longer than standard size costumes; for this costume in custom size, we need about 3 weeks to make it (excluding the shipping time).