Complex sentence: In 1965 Kok married his girlfriend of four years Margrietha "Rita" Roukema (born 1939), Roukema a young divorced mother had two children, a son André (born 1962) who is mentally and physically handicapped, and a daughter Carla.
Split into simpler sentences: In 1965 Kok married his girlfriend of four years Margrietha "Rita" Roukema (born 1939). She was a young divorced mother who had two children, a son André (born 1962) who is mentally and physically handicapped, and a daughter Carla.