Louisa Steenstra and her husband Albert sheltered numerous Jewish people throughout the war. They allowed two at a time to live in rooms they had formerly rented in their spacious home in Groningen, Holland. In 1943 they installed a hiding place they considered undetectable. Their worst fears were realized when a Dutch couple that had been evacuated from their strategically located coastal home, and were living with the Steenstras, betrayed the Steenstra's secret to the Germans.
In the ensuing raid the Germans' dog detected the human presence behind the walls and all was lost. Louisa managed to escape with her young daughter, but the Germans seized her husband and Emanuel Marcus, the Jewish man in the hiding place, and murdered them on the spot.