Found this today online, the details documented below:
“During our investigation of a haunting painting that was posted on GhostGirI’s channel, we documented a Rapid Eye Movement event. This painting, a mourning portrait, or Ars Moriendi, or Memento Mori, part of a centuries old tradition of painting the deceased, depicts a young girl as she appeared in life.
The spontaneous movement of pigment on canvas or in photographs is difficult to document, and usually involves a slow migration of particles over time, which can be measured with time lapse photograhy. Here, before we could set up our lab camera, the movement was captured with a consumer digital camera, and obviously no confirmation measurements need to be taken as the movement was dramatic and witnessed by three people. The canvas is normal, front and back. The stains around the girl are caused by her occasional weeping. Samples this moisture which occurrs about once a month reveal saline.