Anyone else thinking of Monty Python right now?? "I'm not dead!"
I'm happpyyyy! I'm happppyyyy! *conk*
I have to admit that I 1) thought of this as well and 2) was afraid that the situation the thread title described was actually much worse. I thought the opposite etiquette problem had occurred (reading ehell's work etiquette section, as well as sites like retailhellunderground and customerssuck has made me paranoid) . You see, I thought the title was an actual quote from a supervisor/boss/manager!
Before reading this thread I envisioned the poor OP had asked for time off to spend with her sick and dying FIL only to be told something along the lines of not getting time unless it was to go to his funeral!
Yes, I have become horribly jaded and cynical.
Instead, the OP received a touching gesture of sympathy and support...that made an unfortunate assumption and/or reflected a miscommunication somewhere regarding her FILs condition.
I think any response to her employer's good intentions should definitely start with gratitude and appreciation. They can focus on how the good of the company's gesture can be answered by the equally good news that their sympathy was premature and her FIL will get better.
OP you basically get to find a very classy way to convey "Thanks anyway!" Your employer's intentions were good and you get to give them an 'A' for effort. Your gratitude will help smooth away their potential embarrassment at rushing to counsel your grief when you are fortunate enough to have no death to grieve over. Better to have it and not need it than need it and not have it. Do not be afraid to correct them, it was one of the few 'positive' mistakes I have seen an employer make.