He didn't die. And I reckon that would be out-of the books.
Ellis Grey... Meredith's mother. she died because of her Alzheimer disease. You should really watch that episode, its on the end of the 3rd season, or the very begining of the 4th.
When she drowned, you mean? Season 3.
Mark Stoermer. (see picture link below)
September 6, 2008.