The four children and their mother [photo], were found dead on Friday morning and the children’s father, Aaron Cockman, believes the grandfather may have been behind the shooting
Cockman, a local carpenter and builder, said: ‘Peter didn’t snap. He’s thought this through. I think he’s been thinking this through for a long time.
‘All these kids died peacefully in their beds. The (police officer) that went through, he said they looked all peaceful.
‘How the hell Peter did that I still can’t figure out, but if someone did it … he did a good job, he did a really good job.’

‘Their granddad did it’ – Aaron Cockman tells the media, his children’s grandfather planned and executed the mass murders of his family

Mr Cockman had been involved in an acrimonious split with Katrina, which led her and the children to move in with her parents.
He said he had been full of anger after Peter and Cynda Miles cut him off from seeing his children but that had ‘now completely gone’.

Peter Miles [second, left in suit and blue tie], authorities suspect, shot dead his wife, Cynda, [third, back right], his daughter Katrina Miles [left in red dress], and her four autistic children aged from 8 to 13 [front row], before shooting himself

Police forensics investigate the Miles family alleged, murder-suicide in which seven of the same family died in SW Australia

‘I don’€™t feel angry,’ he said. ‘I feel tremendous sadness for my kids.
‘I’€™m tremendously sad but I’ll get through this.’
Cockman said police had told him the children had died peacefully, with Kadyn in his mother’s bed.
Police seized three firearms from the scene on Friday, all ‘longarm’ weapons licensed to Peter Miles. – Longarm weapons are shot from the shoulder, such as rifles or shotguns and are common on farms.
Police are still investigating the circumstances leading up to the worst mass shooting in Australia since the Port Arthur Massacre in 1996.