The Lebensborn project was a program initiated by the Nazi SS with the goal or raising the birth rate of Aryan Children between 1939 and 1945, with the intent on creating "racially pure and healthy" like their parents, who often were unmarried, or married to a Nazi SS Soldier.
During the Nuremburg Trials (1945-1946), it had come to be known that children had been kidnapped to be raised under the Lebensborn Project. (TOS novel: Unspoken Truth)