Complex sentence: Barnet later introduced Richter to his sister-in-law, the painter Helen Sinclair Annand, and the married couple remained together until her death in 1992 after battling multiple sclerosis.
Split into simpler sentences: Barnet later introduced Richter to his sister-in-law, the painter Helen Sinclair Annand, and the couple married. They remained together until her death in 1992 after battling multiple sclerosis.