Complex sentence: His son, Stephan Mark Lascelles, was born on the 26th of November 1980 and his daughter, Moira Christina Sybilla Lascelles, was born on the 21st of February 1983.
Split into simpler sentences: His son, Stephan Mark Lascelles, was born on the 26th of November 1980. His daughter, Moira Christina Sybilla Lascelles, was born on the 21st of February 1983.