Though mold has been ruled out by the toxicology reports, the situation is still "unusual," Winter says, and he speculates that it could have to do with the poor health and habits of the couple.
"At the time of their death, both of them were in very poor health. I don't think they ate correctly or took care of themselves. They didn't seek medical attention," Winter says.
In the months before Murphy died, she, her mother and Monjack were all in Puerto Rico, which Winter says adds another question mark to the investigation:
"Simon and Sharon came down with what they claimed were flu-like symptoms [while there], but they came back and got well with over-the-counter medicines, but when Brittany got sick, she didn't see a doctor and tried to self-medicate," Winter says.
Neal confirmed that the threesome was in Puerto Rico when Murphy was shooting a film, but couldn't confirm the dates or the illnesses.
Many people don't realize how serious and life-threatening pneumonia can be, says Bassett. "It's not as uncommon as people think. If you notice the warning signs… chills, high fever, chest pain, severe cough, night sweats, and breathing difficulties, the best action is to seek medical attention and get the proper treatment."
Bassett also says that when people are chronically ill, the body can stop producing enough red blood cells, resulting in "anemia of chronic illness."
"Acute pneumonia can come on fairly quickly. The bottom line is we're very aggressive when people have this. It needs to be treated promptly," he says.