dr. karen roos. >> she said that she loved pittsburgh. she loved her patients. that the people of pittsburgh were wonderful, and she was so happy to be there. >> reporter: autumn had always intended to be a care-giver. her cousin, close as sisters, sharon king remembers that even as a little girl she administered playtime tlc. >> we had a doctor's office. and our patients were our stuffed animals. >> reporter: and dr. autumn klein was holding clinic hours, huh? >> she was the doctor. >> reporter: it was an interest that took root early for autumn and never left. always a top of her class student in the baltimore area, she later got her undergraduate degree in neuroscience from amherst. >> helping people was the main thing. she was just so smart, so intelligent, so thoughtful and so caring. >> reporter: you and your husband must have been very, very proud of her. >> we were. >> reporter: lois klein is autumn's mom. >> we knew that she was putting her mind on her studies, and we were giving her the best education we could possibly give her, and she was taking adva

dr. karen roos heard about it, she knew, right away, her friend had suffered an agonizing death. >> as al, i know about how people die of cyanide poisoning, and i couldn't dwell on that. >> reporter: and just as in an old agatha christie cozy murder mystery about a cyanide poisoning in the village, the inspector was about to call. pittsburgh's senior investigators were enroute to talk to robert ferrante. did he have any idea how cyanide found its way into the bloodstream of his late wife? >>> coming up. a husband's theory of how, and why, his wife died. so what'd he say? "why would she do this to herself?" >> reporter: what was he suggesting? and did he know something that police didn't? ing neutrogena hydro boost water gel. instantly quenches skin to keep it supple and hydrated day after day. formulated with hydrating hyaluronic acid which retains up to 1000 times its weight in water. this refreshing water gel plumps skin cells with intense hydration and locks it in. for supple, hydrated skin that bounces back. new hydro boost. from neutrogena. it's time to change the way we clean. and