The man had rung the doorbell of the house in the northern town of Schwanewede near Bremen on Monday evening, and forced his way in.
Wearing a balaclava and a long black coat, the man had the terrified babysitter at gunpoint when the children she was looking after, came downstairs.
When they offered him their savings, he was obviously overcome with shame and left the house without a word – or a cent.
“The children had heard what was going on from upstairs and came down with their money, all their savings,” a police spokesman told The Local on Wednesday.
He said he was not releasing the ages of the children in order to protect them from being identified, but that they were both younger than seven.
“The robber must have realised what he was doing was awful, and simply put his gun away and left,” said the spokesman.
The authorities are now looking for the would-be robber, described as in his early twenties, 185 centimetres tall and thin.