A woman has been found guilty of poisoning her husband in an attempt to confuse him while she stole £43,000 from his mother.
Heather Mook, right, also poisoned her daughter
Heather Mook, who denied the charge, had a previous conviction for poisoning her seven-year-old daughter in 1982.
Mook, 57, of Heslington Road, York, was described as "deceitful and dishonest" at York Crown Court.
She was found guilty of two counts of poisoning so as to endanger life. Sentencing was adjourned for reports.
A jury took two-and-a-half hours to find her guilty of poisoning John Mook, her fourth husband, with an anti-depressant drug.
She had already admitted a number of other charges, including giving her husband rat killer and other theft-related offences.
She was cleared of four counts of endangering her husband's life by administering the anti-depressants.
Judge James Spencer QC told Mook a jail sentence was "inevitable".
The jury had heard Mook tricked her husband into taking the tablets - as many as nine on one occasion - by telling him they were muscle relaxants.
While he was in hospital recovering from the poisoning she again tricked him into taking more tablets.
Mr Mook's daughter, Tracy Hardwick, earlier told the jury how she had been "totally shocked" when visiting Mr Mook in hospital.
'Fishing and driving'
She said: "He was lying on a mattress on the floor staring at me pretending he was fishing and driving a bus."
She said his condition had baffled hospital staff, with a number of tests coming back negative before eventually showing he had suffered an overdose of anti-depressants.
The court heard Mr Mook had often complained of feeling tired and unwell, but put it down to a prostate problem he was suffering.
Speaking after the verdict, Insp Nigel Costello said Mook had gone to "extraordinary lengths" to make sure her husband did not discover her theft.
The money stolen from Mr Mook's mother, Freda, had been intended to pay for the cost of her residential nursing home.
Police said Mook may have squandered the money on holidays or used it to pay off a debt she had incurred before meeting Mr Mook.