Jack Nagel met Gitta Ehrenfreund on Dec. 25, 1954, in Los Angeles. He was a 33-year-old importer of Swiss watches. She was 19, a pre-med student. Within four days, they were engaged. They married three months later.

It may have been abrupt, but Mr. Nagel had lost his youth and most of his family to the Holocaust, and now he was eager to start a new family. He moved to Los Angeles, began building tract houses and later branched into apartments and office buildings.

Mr....