Not nearly as much is known about Lydia as is known about van Vogt's first wife, Edna Mayne Hull. However, there are a few known details about her life.
Lydia Bereginsky was born on April 18th, 1927 in Vienna, Austria. (I know nothing more of her early life.) She was previously married to a man with the surname Brayman, and they had at least two children, Gregory and Marlene. Her son, Gregory, collaborated with his step-father on an outline for a proposed sequel to Slan in the 1980s. Entitled Slan II: The Tendrilless War, this novel was eventually completed by Kevin J. Anderson, and published as Slan Hunter.
Her colorful assortment of careers included modeling and being a court interpreter specializing in Russian. It was because of her interpretor work that van Vogt first met her. In the late 70s he was doing research into the major languages of the world, a project that in part resulted in the No-Time series of language-learning tapes. Part of his research involved finding native speakers through classified ads in Los Angeles newspapers, and then tape-recording samples of the spoken language. Lydia answered such an ad, and in the course of her recording sessions they became friends, a relationship that carried them into marriage.
Beginning in the early 1990s van Vogt's Alzheimer's symptoms and poor health seriously handicapped him. She took up the role of dealing with fan mail, arranging convention appearances, caring for him, and accompanying him wherever he went. A compassionate and generous woman, she was widowed on January 26th, 2000 when van Vogt died from pneumonia-related causes.