According to OpenStreetMap, North Fork Cowiche Creek is a tributary of South Fork Cowiche Creet for a short distance before Cowiche Creek starts. This seems odd.
Diana Frances Spencer was born on 1 July 1961, the fourth of five children of John Spencer, Viscount Althorp (1924–1992), and Frances Spencer, Viscountess Althorp (née Roche; 1936–2004).