What is incomprehensible about it? The husband was suffering from depression and mental illness and murdered his wife and two children before taking his own life. It is a repeat of what we have at WHF.
There's no evidence prior to the attack he had mental illness. He told his GP he didn't have suicidal ideation.
As for the White House Farm murders, for someone who claims to be far more forensically aware than the rest of us you do write some drivel. Sheila was suffering from schizophrenia and postpartum depression, the latter not considered by doctors to last longer than three years. She responded to treatment. You have never produced a forensic link to her as the perpetrator.
Re: Clonroche. I'm surprised you haven't accused Lorraine Flood of the murders. After all, trace of antidepressant medication was found in her system.