Jarvis of Western Australia

Does anyone know of and/or the whereabouts of the descendants of Hope (nee Jarvis) and George Wilson, last of Western Australia ? She played drums in their band; he was a pianist. They had at least two children.. Faith and David, b. c. 1940's. They are my second cousins, and I would like to make contact with them. Hope's parents were Albert Shaw and Adelaide Jarvis. Albert was born in South Australia in 1879.