Maggie Carmichael wasn’t developing like other kids. As a toddler, she wasn’t walking and had a limited vocabulary for her age. She was diagnosed with PMM2-CDG, potentially fatal gene mutations that cause abnormal enzyme activity — and affect fewer than 1,000 people worldwide. Her parents, Holly and Dan Carmichael, raised $250,000 for scientists to screen existing drugs to find a potential treatment, and in a single-patient trial with Maggie as the test subject, one drug showed promising results. The young girl stopped face-planting when crawling, she began using a walker instead of her wheelc…