Please can you help Jack aged 8 get to America

We are trying to raise £20,000 to take our son Jack to America for vital research and to see one of the top neurologists to see if we can get Jack's seizures under control
Jack was diagnosed with Mowat Wilson Syndrome in April of 2012, other confirmed diagnosis’s are Global Development Delays, Gross Motor Disorder and Brain Atrophy which was picked up on an MRI scan. Jack suffers life threatening seizures and has to go into resus every time he has one.
Jack doesn’t talk, has to have all food pureed, can't feed or dress himself, is doubly incontinent, in fact he is totally dependent on adults. All this said and done and he can now crawl, clap his hands and waves hello & goodbye as well as signing money and bird. Jack can also drink out of a feeder cup and on Christmas Eve 2015 Jack took his first unsteady independent steps. He always has a big smile for everyone.