I was researching the Dresden Files, and I know that the TV series doesn't follow the books very well. One subject was Harry's father and his death. In the books, how did Harry's dad die?
Malcolm Dresden died of brain aneurysm. From Storm Front:
I never got to be old enough to be his assistant, as he had promised me. He died in his sleep one night. An aneurysm, the doctors said. I found him, cold, smiling. Maybe he'd been dreaming of Mother when he went. And as I looked at him, I suddenly felt, for the very first time in my life, utterly, entirely alone. That something was gone that would never return, that a little hole had been hollowed out inside of me that wasn't ever going to be filled again.
In Fool Moon, there's also this:
Chauncy's eyes gleamed with avarice. "Didn't you know about your mother's past, Mr. Dresden? A pity that we didn't have this conversation sooner. You might have added it into the bargain we made. Of course, if you would like to forfeit another name, to know all about your mother's past, her..." his voice twisted with distaste, "redemption, and the unnatural deaths of both mother and father, I am certain we can work something out."
I gritted my teeth in a sudden rush of childlike frustration. My heart pounded in my ears. My mother's dark past? I had expected that she was a wizardess, but I had never been able to prove anything, one way or another. Unnatural deaths? My father had perished in his sleep, of an aneurism, when I was young. My mother had died in childbirth.
Or had they?
The truth or otherwise of that hasn't been established.