Did you fill your date of birth on any age-protected content (websites for distilleries or breweries, for example) as 1st January 1940 or something? They could just mistakenly believe you're 81 based on that :)
In this case, the above commenter could be doing things signaling that he may need a will soon due to diseases or life situation that he is not aware of. Or he/she has looked into content similar to those people in need. ¯\_(ツ)_/¯
In this case, she knew she was pregnant. Her family didn't.
Other than that I have no idea heh.