Let me also add, my wonderful Aunt is in this category. She will believe absolutely anything she sees posted online.
She is in her late 60s. Her husband, my uncle, died in 2015. She's very lonely. She spends almost all day on the computer. She use to be totally different. Thank God she mostly only reads things and believes whatever she reads. She does very little sharing or spreading of the stuff herself online.
At Christmas again this year, she was talking about how aliens are hiding behind the moon and running our utility systems. She also thinks- I swear to God above- that Donald Trump is working with them. I don't even ask for details. We just nod when she talks and try to get her to change the subject. She doesn't even realize that when she starts talking like this at our Christmas gathering that people try to leave the room or leave where she's sitting or standing. When she is talking about other things- normal things- she's completely rational and sounds fine. I got her to talking about a trip she took to New York city about 10-15 years ago and got her mind off her nonsense and she was fine.
her daughter, my first cousin, is a wonderful person. She's a medical professional and a very good one. All she can tell us is to ignore her and let her talk and there is nothing we can do about it.