Aaron Cockman is the father of four children who were found dead on a property with their mother, grandmother and grandfather, in what is believed to have been a murder-suicide, near Margaret River in Western Australia's south on Friday. Cockman, who was estranged from the children's mother and her family at the time of the shooting, has spoken publicly for the first time since since the tragedy, Australia's worst mass shooting since the Port Arthur massacre

• If you or someone you know is impacted domestic or family violence, call 1800RESPECT on 1800 737 732 or visit 1800RESPECT.org.au. Mental health crisis support services can be reached 24 hours a day: Lifeline 13 11 14; Suicide Call Back Service 1300 659 467; Kids Helpline 1800 55 1800; MensLine Australia 1300 78 99 78; Beyond Blue 1300 22 4636