Weird extra member in facebook group chat?

[Nick]

have you ever sent an email to a recipient but you spelt their name wrong? this returns an error message from the user "mailer-daemon" to tell you the message did not send to the person you wanted to. my best guess is that facebook has the same thing to tell you whether or not maybe the person you're trying to message has delted their accout or simply never had one. there's no cause for concern here, nothing is going to happen and nobody is certainly spying on your messages.