Stanisław (b. 1887) and Pelagia Vogelgesang lived in Węgrów near Warsaw. Pelagia worked as a teacher, and her husband was the school headmaster. The Farbiarz family also lived in the same town: Szmuel (1910–1943), who worked as a carpenter, and his wife Fajga (1912–1943). In 1939 she gave birth to the second daughter, Lusia.
In 1941 Germans established a ghetto in Węgrów, where Jews were resettled from the town and surrounding areas. Over a year later, the ghetto was liquidated. Around 1000 Jews were murdered on the spot, the rest died in the Treblinka extermination camp. The surviving small group of Jews, who were forced to clean the ghetto area, were shot in May 1943.
On May 1 Pelagia heard a baby crying. Lusia Farbiarz was sitting on the threshold of her house. Pelagia immediately took her home and took care of her.
The Vogelgesangs had to face the suspicions of Germans and Polish neighbours. Doubts were raised by Pelagia's maiden name – Jakubowska. Then Pelagia showed the documents proving that she was not Jewish. When she was registering Lusia, the girl was interrogated at the police station to determine whether she was a Jewish child.
For some time Pelagia also helped the girl's uncle, Chaim Farbiarz – she would leave him food at a designated place. She also hid the local miller Klejman and his child.
After the war, Lusia went to school. But when her uncle Henryk (Enrique) Farbiarz (b. 1918) returned from the Soviet Union, the Vogelgesangs had to part with the girl. It was very painful for them.
In her statement Pelagia wrote: "I instilled best principles in her. Lusia knew very well that I was not her mother, but she also realised that I saved her life and had every right to love her".
The girl went to Argentina with her uncle, studied at the University of Buenos Aires and started a family there as Luisa Popovsky. In the 1980s Pelagia still hoped to see her Luisa once again.
In 1984 the Yad Vashem Institute awarded Pelagia Vogelgesang the title of Righteous Among the Nations.