When the Nazis ripped his family from their home in Poland, Ben Stern survived the ghettos and the concentration camps by never losing faith in human kindness.

So now, at the end of his life, the 95-year-old has found an almost perfect antidote to how he was treated by the Nazis: Opening his California home to one of their descendants.

His roommate, Lea Heitfeld, is a 31-year-old German student at the Graduate Theological Union in Berkeley, whose grandparents were active and unrepentant members of the Nazi Party. Rather than shy away from her family’s history, it has inspired her to learn about Jewish people and educate others about their religion and what they endured during the Holocaust. She’s even getting her master’s degree in Jewish studies.

Welcoming Heitfeld, the kin of the very people who brutally forced him from his childhood home, to live as his roommate while she finishes her degree feels like “an act of justice,” Stern said in an interview. “It was the right thing to do. I’m doing the opposite of what they did.”