My mom has early dementia and seems normal at times but as the day progresses, she get more confused. She believes she has eye cancer and has to have surgery. She does not. Dad brought her to the eye doctor recently to update her glasses. How to handle? If I say, "No mom, you don't have eye cancer." she doesn't believe me and gets frustrated but I'm afraid if I agree with her she will get more worked up and scared. She's constantly talking about the surgery and how she's worried.