The Tv veteran's adopted son, Michael Hawley, reveals the 70 year old - who famously voiced teacher Edna Krabappel on the longrunning cartoon - had been struck by a slew of health problems this year (13) after learning the breast cancer she had successfully battled in 1985 had returned.
She underwent surgery in March (13) and had been in recovery this summer (13), when she tripped over her cat at home and broke her back, leaving her in serious pain and bedridden for weeks.
Hawley tells the National Enquirer, "She was suffering from multiple health problems. It wasn't just the cancer that killed her. Her body had taken a beating and it just gave out."
However, Hawley reveals his mother tried to remain in positive spirits throughout her personal troubles.
He adds, "Mum was always so upbeat, even in the worst of times. She told me, 'If you approach the world with joy and love, you'll leave it a better place.' And she did."