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Although Brittany Murphy's mother scoffed at speculation last year that toxic mold might have contributed to the starlet's death, she's now claiming that toxic mold was the culprit, and she has launched a lawsuit against her former lawyers for allegedly preventing her from filing a wrongful death case.

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The "Clueless" star passed away in 2009 after suffering a cardiac arrest linked to pneumonia and anemia, while Murphy's husband, Simon Monjack, died five months later from the same causes.

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Sharon Murphy is suing her former lawyers for legal malpractice, claiming they duped her into agreeing to a settlement and giving up her rights to sue the property builders.

She alleges the attorneys persuaded her to accept a settlement over construction problems in January but failed to explain to her that she would then be unable to take action against the builders.

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TMZ claims she is seeking the amount she would have won in a wrongful death lawsuit, as well as other damages.