Daughter, Granddaughter Guilty Of Woman's Murder - 1991-08-23

The daughter and granddaughter gave separate statements to police telling how they had chopped up 50 capsules of Dilantin, an anti-seizure medicine, then mixed it in clam chowder and fed it to Van Sickle Nov. 17 in the family home in Rainier Valley.
But when she was still alive the next day, they put a pillow over her face and suffocated her. After a 20-minute struggle, Van Sickle died.
A medical examiner concluded she died of congestive heart failure, and her body was donated to the University of Washington.
"This was the perfect murder - with the one exception - a guilty conscience," John "Jay" Mooney, a Seattle homicide detective, said after the verdict.
Wikipedia cite:
{{cite news | first = Julie | last = Emery | title = Daughter, Granddaughter Guilty Of Woman's Murder | url = http://community.seattletimes.nwsource.com/archive/?date=19910823&slug=1301446 | work = Seattle Times | date = August 23, 1991 | accessdate = August 8, 2019 }}