My mother-in-law is 85 years old and I am her caregiver. She picks her nose in front of family, friends. Several have asked her to stop doing that because it grosses them out, she will stop for a few minutes and than continue. It's to the point that I can't have people over for dinner because she will go and pick up food with her hands, no one will eat from whatever plates she gets food from. I have kindly asked her to stop but it seems she doesn't care. Please help?