Nellie (pictured), from Brighton, was diagnosed with metachromatic leukodystrophy - a rare genetic disease causing severe damage to the nervous system and organs.
last year, zolgensma, a highly effective treatment for the rare genetic disorder spinal muscular atrophy was approved for use on the nhs. it s the world s most expensive drug and has the potential to save the lives of babies with the condition. one year old edward was given the drug in august and it s changed his life. zoe conway has been to meet him and his mum megan. he s just my little boy, just completely in awe of him, he s like the strongest little baby i know. i m just so proud of him. he s just doing so well. edward was born with the genetic condition spinal muscular atrophy. it causes progressive muscle weakness. as a baby, edward became floppy, he couldn t move his legs. doctors feared that one day he might lose the ability to breathe. and then along came the most expensive drug in the world zolgensma.