An 80-year-old woman died one month after her Sleep Number bed suddenly moved without warning and trapped her against a wall for two days last year, a new lawsuit alleges.

A woman has filed a wrongful death lawsuit against Minneapolis-based Sleep Number Corporation and Leggett & Platt, Inc. — the company that manufactured the bed's base — after her mother became trapped between the mattress and the wall for two days and died a month later of her injuries.