Desmond Gore, 73, was found guilty of 20 charges of sexual abuse, including the rape of three eight-year-old girls, at the Perth District Court in Australia on Tuesday.
One of the victims afterwards wrote: “I feel safe when loved. I feel sad when I have sex with my grandad.”
The horrifying abuse took place at a home in the suburb of Armadale in south-east Perth from 2007 to 2010.
It first came to light when the Department of Child Protection was told a child in Gore’s care had been sexually abused.
She was removed from the house but Gore and his wife were still allowed to take children into their care.
He sexually abused six kids in total including five who were under his roof, the court heard.
In 2013, a case worker found the disturbing note in a box of possessions.
Its author said that Gore, a former painter, would rape her when his wife was out of the house.
He denied the allegations and said they were “complete and utter lies”.
“I feel safe when loved. I feel sad when I have sex with my grandad”
Gore told the court: “It’s all about the money, nothing else.”
He claimed that he couldn’t have raped the children as he was impotent at the time.
However, the jury convicted Gore after a day’s deliberations on 20 out of 21 charges.
The rapist will be sentenced on Friday and has had his bail revoked.