Xeno, Yves, and Zahara are best friends celebrating one of their own birthdays. They make the following statements:
Xeno says, "It's Yves' birthday!"
Yves says, "It's not Xeno's birthday!"
Zahara whispers, "It's __'s birthday", but so quietly that you can't make out which of the three names she said.
If I told you how many true statements were made, then you still wouldn't know whose birthday it is. Now that you know that, if I told you what Zahara said then you'd know whose birthday it is.
Whose birthday is it?