Even in August 1939, before the start of »Aktion T4«, an official notification requirement for children up to the age of three with mental and physical disabilities was introduced in Germany. The »Reich Committee for the Scientific Registering of Serious Hereditary and Congenital Illnesses« acted as the central office that recorded and organised the »child euthanasia«. In the »Chancellery of the Führer«, there arose a panel of experts headed by Viktor Brack, to which the paediatricians or psychiatrists Werner Catel, Hans Heinze (1895–1983) and Ernst Wentzler (1891–1973) belonged. On the basis of the file in question, the panel decided on the admission of the infants and children to »children's ward for expert care« established in paediatric clinics or hospitals and nursing homes, where, after an observation period, the girls and boys were killed by means of overdosed sedatives or food deprivation. 

The first of these »children's wards« was formed in the State Hospital Brandenburg-Görden in June 1940; this was followed by more than 30 further such facilities throughout the Reich. Of the approximately 20,000 children evaluated by the »Reich Committee«, up to 5000 of them died, among them Wilhelmine Haussner and Alfred Wödl.

However, the »euthanasia« crimes committed against children and adolescents included not only the murders in the »children's wards«. Around 4,200 underage patients of psychiatric institutions were murdered by gas in the context of »Aktion T4«, their bodies being, in part, misused as medical research objects, such as that of Werner B. In addition, a large number of children and adolescents had fallen victim to the decentralised »euthanasia« by 1945.