Joseph Kushner, grandfather of Jared Kushner, was born in October 1922 to Chana and Moshe Berkowitz. In August 1945, he married Reichel "Rae" Kushner (February 27, 1923 – 2004) in Budapest. Rae Kushner is from the city of Navahrudak, and is remembered for their participation in the escape (via digging a tunnel) from the local Jewish ghetto established by the Nazis. In an area where about 10,000 Jews lived before World War II, about 550 survived. The story of Rae Kushner and her brother Honie is on display in the local Museum of Jewish Resistance, for which Charles Kushner was the chief benefactor. The Kushners came to the US as Sh'erit ha-Pletah from the USSR in 1949.

The Joseph Kushner Hebrew Academy and the Rae Kushner Yeshiva High School, both in Livingston, New Jersey, are named in their honour.