There have been several family dynasties amongst members of the Western Australian Parliament.

Sir Charles Court and Richard Court were the first father and son Premiers in Western Australia.
The Holman family is represented by three members, all elected to the seat of Forrest. Jack Holman represented Forrest for the Labor Party from 1901 to 1921 and from 1923 to 1925. His daughter, May Holman, was also member for Forrest (1925-1939) and was the first woman to represent the Labor Party in any Parliament of Australia or the British Commonwealth. After her tragic death in a motor vehicle accident, her brother Ted won the seat in the subsequent by-election.
Edith Cowan, as the first female member of Parliament, was the cousin of Sir Edward Wittenoom, MLC (1894-1934) and great-aunt of Hendy Cowan, member for Merredin–Yilgarn (1974-2001).
For further information, see Members of Parliament – family dynasties.