Louis Marx

Marx married his first wife Irene Saltzman, nicknamed René, on December 31, 1927 in Manhattan, New York. They had four children. Rene died in April 1944 of breast cancer at age 37. Marx became very depressed at this time and suggested he might quit the business to take care of his four children.

On March 30, 1947, Marx married Idella Ruth Blackadder, Louis' chief jewelry designer for his Charmore line and nearly 28 years his junior. They had five children.

Marx's daughter, Patricia, was born in 1938. She went on to become an activist author, and the second wife of Daniel Ellsberg, assisting him in the release of the Pentagon Papers in 1971. Louis Marx, a strident anti-Communist and supporter of Richard Nixon, regarded Ellsberg as a traitor afterwards.

His eldest child, Barbara Marx Hubbard (1929–2019), was a New Age futurist Barbara's daughter, Alexandra Morton, is a notable marine biologist.

Marx's son, Louis Marx Junior, is a venture capitalist and philanthropist who has contributed to the arts, education and medicine. One such example is the Louis Marx, Jr. Center for Children and Families of New York.

Jacqueline Marx Barnett was an artist, maker of paintings and prints.

With his last wife he had 5 sons. They were named after prominent WWII American and international military figures, with whom Marx had close association during that time period.