The family of former U.S. Rep. Eddie Bernice Johnson said Thursday that the trailblazing Texas congresswoman, who died over the weekend at age 89, passed away after getting an infection and accused a Dallas rehabilitation facility of neglect.

Johnson, who was the first registered nurse elected to Congress, died on Dec. 31 at her Dallas home. Les Weisbrod, her family’s attorney and Johnson’s longtime friend, said at a news conference that her death was caused by an infection in her spine that developed after she was left in her own feces at Baylor Scott & White Institute for Rehabilitation following back surgery.

Weisbrod said he has given notice to Baylor Scott & White Health System and Baylor Scott & White Institute for Rehabilitation that the family intends to file a lawsuit for medical negligence over her death.