Task: Question Answering
Input (English): Context: Get this : I went home yesterday and then returned to Riverdale earlier today , meaning I was home for less than 24 hours . This is not the story I want to tell though . While I was home , I was sitting around in our family room at around midnight , and on the side table next to the couch I see an envelope from Ana , who is my aunt because she married my Uncle Robby . I was curious as to what she had sent us , because she generally would n't need to send us mail . 
Question: What about Ana sending the mail caused the speaker to feel so surprised ?
Output (English): Ana has almost never bothered to write them , so this is an uncommon occurrence.