My twin brother and sister live together in a house they bought together and they go on vacation and do everything else together, and neither of them ever goes out on a date. They have separate bedrooms, but still I have to wonder. They act more like husband and wife.
Queenie, is this something the rest of the family should worry about?—Older brother
It is not unusual for a single brother and sister to share living quarters, and there is a much stronger bond between twins than other siblings.
Have you mentioned to them how things look to you and asked them about your concerns? They may be offended, but whatever their response is, it will give you some idea what is or is not going on.
And after all, they are adults and it is really their business and nobody else’s.