Linda
Delusions and hallucinations are common with Lewy Body. It is futile and not helpful to try to convince them they are not real. To them they are very real. Someone suggested to me to simply and calmly assure your LO that you love them and will protect and care for them from anything that comes along. This has worked for us most of the time. There are some meds that can take the edge off the delusions and/or hallucinations if they are really bothersome. You can check with neurologist. My DW also wants me to sit right beside her all day. I have found telling her to "hold that thought a minute" I have to go do something (could be anything) and I'll be right back. By the time I get back she has forgotten about it. I know this is all happening fast for you, but you have good instincts on caring for your sister. Breath, you are doing great and she is lucky to have you there.