Her father found a letter that redditor judokitten had written to the Tooth Fairy years ago, on the occasion of losing a tooth and not getting the expected reward. She tells the story in the comments:
Full story. So, I had lost a tooth, but I was suspicious about the actual validity of the toothfairy's magical abilities. So, I didn't tell anyone about the lost tooth. Lo and behold, she did not arrive.
The next morning, I loudly proclaimed the toothfairy bullshit in my 9 year old terms, and my mom told me to write her a letter expressing my displeasure.
I was returned a letter that basically said,
"I couldn't get to your pillow the night before last because I got stuck in all the mess. Maybe if you clean your room, I could get to you in a timely manner."
Well played, tooth fairy. Well played.
Although the post title mentions the letter is passive-aggressive, there is nothing passive about either the daughter or the mother’s Tooth Fairy's response. Incidentally, I was impressed that, even though her handle is judokitten and the letter is signed “Jennifer,” many commenters still assumed the letter-writer was male.