Complex sentence: His father was the Duke of Kent, fourth son of King George V and Queen Mary, and was killed in a plane crash near Caithness, Scotland, on 25 August 1942, just six weeks after his third child was born.
Split into simpler sentences: His father was The Duke of Kent, the fourth son of King George V and Queen Mary. The Duke of Kent was killed in a plane crash near Caithness, Scotland on 25 August 1942, just six weeks after his third child was born.