Marries Marietta Kövesi, also of Hungarian Jewish background. They met while von Neumann was still living in Europe.

His daughter, Marina von Neumann Whitman, is born. Marina later becomes a prominent economist and academic. She was one of three women who served on the Council of Economic Advisers.

Divorces Marietta Kövesi. The reasons for the divorce are not publicly documented, but it occurred after several years of marriage.

Marries Klara Dan, whom he met in Budapest. Klara Dan played a crucial role in his later work, particularly in programming the ENIAC and MANIAC computers. They remained married until his death. Klara assisted von Neumann in editing many of his writings.

Known for his charming personality, wit, and ability to rapidly grasp complex concepts. He enjoyed socializing and hosting parties. While he was deeply admired for his intellect, some found him intimidating. He had a generally jovial attitude.