Complex sentence: The couple divorced in the early 1960s, and, shortly thereafter, he married his second wife, Jeanette J. Hopper and whose son, Gordon P. Williams, became Hopper's stepson.
Split into simpler sentences: The couple divorced in the early 1960s, and, shortly thereafter, he married his second wife, Jeanette J. Hopper. Her son, Gordon P. Williams, became Hopper's stepson.