Children with Hirschsprung's Disease (HSCR) have no normal nerve cells in the lower end of their bowel. This can cause babies to die if left untreated treated. Currently the part of bowel that doesn't have normal nerves is removed with an operation, but this can have long-term complications including needing a permanent bag on the tummy for poo (stoma). Because of this there is an urgent need for better treatments. The investigators have found that children with HSCR have nerve stem cells throughout their bowel, even in the lower end where the nerves haven't grown normally. We can grow these stem cells in the laboratory to form balls of nerve cells (neurospheres). The investigators want to find out whether these neurospheres grow into the nerves that are needed for the bowel to work normally. First the investigators will see how the nerve stem cells from the lower end of the bowel grow compared to those from the normal bowel. Then the investigators will see if the neurospheres change when the investigators put them with medications that affect growth of bowel nerves. At the end of this project the investigators hope to know whether the nerve stem cells at the lower part of the bowel in children with HSCR can turn into bowel nerve cells that might make the bowel work normally. The investigators also hope to know whether the investigators can use medications to make the stem cells turn into normal nerves, meaning that children with HSCR could avoid an operation and a stoma.