Brittany Murphy‘s mother says her daughter was killed by toxic mold that was found in the Hollywood home where she lived with her husband, Simon Monjack. It was at first believed that Monjack died of a heart attack just five months after Brittany passed away, but a coroner’s report later showed the cause of death was acute pneumonia and severe anemia, the same symptoms Brittany had at the time of her death. Sharon Murphy believes the people who built the house should be held accountable for the mold that caused their deaths — but according to a new lawsuit, Sharon claims her lawyers convinced her to accept a settlement for construction defects last January. She says she didn’t realize she was giving up her rights to sue the builders for wrongful death, so now she’s suing her former lawyers for legal malpractice and is going after them for whatever she would have won in a wrongful death suit.