Thanks. She's decided to just wait and see, since it's all she can do, and at this point there doesn't seem to be any way to know more. Her anticipation was fueled because we got our stimulus payment back on April 15th, but we file taxes every year, so fall into a different category of recipient. Sis is thinking, "Well, I'm a nobody. So, what do they care about me?" Frustrating for her, certainly.
The thing about receiving it when she got her regular SS payment came from friends of hers, who really have no way of knowing anything. My sister trusts her friends a lot, and tends to adopt their opinions as fact, something that makes me more than a little crazy sometimes. (Her friends come up with some pretty wild theories about all sorts of things, so I tend to ignore a lot of what they say, and I regularly have to talk logical sense into my sister.

)
That your friends have received their stimulus money is the strange part. Can you ask them what their SSN numbers end with? My sister's SSN ends in 9, which is why I was thinking she'd be among the last to get a payment, since somebody (might even have been here) said payments were being made by SSN order.
All in, we wait and see. I'll be sure to share when and if it happens.
Dave