A monstrous father who stalked and murdered his two children as they cowered under a desk left a suicide note blaming his estranged wife for his cowardly crime.

John Edwards, 67, killed his daughter Jennifer Edwards, 13, and his son Jack, 15 in West Pennant Hills in Sydney’s north-west on July 5, 2018.

The children were found “crumpled together” under Jack’s bedroom desk with multiple gunshot wounds.

Edwards then committed suicide at his rented home near Normanhurst on the night of the murders, with investigators later stumbling across a USB-stick near his body containing a note for the mother of his children, Olga.

Before shooting himself dead, the psychotic killer also hung a “World’s Greatest Daddy” shirt on a chest of drawers at the end of his bed.

“Olga you may scream out what has John done when the reality is what has Olga done,” the three-page suicide letter began, the Daily Telegraph reports.

“None of this had to happen had you been a halfway normal person.”

Only six months after the crime occurred, Olga took her own life.

An inquest into the deaths began last week and NSW Coroners Court heard Edwards had “a propensity for domestic violence”, including physical and psychological assaults against the women in his life and his children.

His ex-partner’s came forward, with one saying he wasn’t physically violent towards her but was “controlling”.

Another said he was “unbalanced and a narcissist”.

Some of his controlling behaviours including forcing them to wear lipstick and mini skirts, and giving them the silent treatment for weeks.

He also used to keep a tight hold on finances.

Including the two he murdered, Edwards had 10 children to seven partners.

He treated two of his former partners lives and gave another rat poison, while his other kids recounted being beaten with a belt and cattle whip.

Edwards was given a licence to shoot rifles and pistols in June 2017 after NSW Firearms Registry staff used a police database report that had failed to pick up several matters related to domestic violence.

This article originally appeared on Over60.