It is not body armor.
If someone wanted her dead they would do the head shot with a crack sniper and they would not care at all if they hit anyone else around her. She has no head protection.
Someone on another thread posted a photo of a therapeutic vest that is designed to stimulate the lungs and prevent the buildup of fluid in them. This seems like a credible possibility in light of the fact that she seemed to have pneumonia for months at a time in 2016.