J. G. Mattison interaktyvus medis
1986–♂ Benjamin Keith Roydhouse
–♀ Emma Evans
1989–♂ Gavin Paul Roydhouse
1953–♂ David John Roydhouse
1953–♀ Wendy Barbara Porter
1920–2001♀ Eileen May Mattison
1924–1990♂ Keith Roydhouse
–♂ J. G. Mattison