The Pennsylvania attorney general’s office plans to test DNA from a hair found on a wipe that was pulled from the throat of a woman who lived at a care home for people with developmental difficulties.

The testing is part of a renewed criminal investigation into Cheryl Yewdall’s choking death in Philadelphia nearly three years ago, according to court documents filed Thursday.

A $15 million wrongful death lawsuit filed by Yewdall’s mother casts suspicion on an unidentified staff member at the Merakey Woodhaven facility in Philadelphia. Attorneys for the family recently asked a judge to order DNA testing on a strand of hair that was stuck to the corner of the wipe — a potentially important piece of evidence missed by city homicide investigators. A pathologist for the family detected the hair by magnifying police evidence photos of the wipe.