Forensic-pathologist-to-the-stars Cyril Wecht, who has worked on such cases as JFK and Elvis, performed a second autopsy on Anna Nicole Smith's son, Daniel, on Sunday, but was unable to determine the cause of death. As such, he has ordered further tests, including a toxicology screen, that will take weeks to complete. Wecht, however, ruled out several potential natural causes, including heart disease or a stroke, and didnt find anything suggesting foul play/traumatic injury/poisoning.