Ground-breaking TV documentary followed Some 15 children in medical trials . They were the first in world to have pioneering treatment immunotherapy . It uses powerful drugs to kill off cancer cells and destroy bone marrow . Toxicity of immunotherapy means children often need to be sedated . In the film , the children 's parents reveal why they decided to take part . The documentary , Raining In My Heart , will be shown on ITV on April 15 . Raining In My Heart will be shown on ITV on April 15 .
Ground-breaking TV documentary followed three children in medical trials . They were the first in world to have pioneering treatment immunotherapy . It uses powerful drugs to kill off cancer cells and destroy bone marrow . Toxicity of immunotherapy means children often need to be sedated . In the film , the children 's parents reveal why they decided to take part . The documentary , Raining In My Heart , will be shown on ITV on April 15 . Raining In My Heart will be shown on ITV on April 15 .