Mr Wogersien found details of a confession by SS doctor Helmut Kunz at a 1959 trial not covered by the press. After the trial he walked free.
Kunz told the court: "Magda Goebbels said, 'I need your help in the killing of the children.' I refused her. But she insisted and afterwards declared it was no longer a request for help, 'but a direct order from Hitler'."
He said he tried to escape the bunker, "but Magda found me and said if I didn't return, 'you will be a dead man'." He was forced to go with her.
He recalled: "The children were all in one room, but they were not asleep. 'Have no fear,' said Magda. 'The doctor is going to give you an injection all children and soldiers get.'
"She left the room. I injected them with morphine. Magda Goebbels went into the room, the cyanide capsules in her hand. She stepped out, crying, saying; 'Doctor, I can't do it.