The Letter is a quest item in The Legend of Zelda: Link's Awakening. It is part of the trading quest for the Magnifying Lens. Christine, the lady goat in Animal Village, has written it for her pen pal, Mr. Write, but has no way to send it to him. She will refuse to talk to Link if he does not treat her like "a lady" by giving her flowers. If he gives her the Hibiscus, she gives him the letter in exchange and asks him to deliver it for her. The letter can, in turn, be traded for the Broom.
Included in the letter is a picture of Princess Peach from the Mario series, rather than one depicting Christine. The reason for this is left ambiguous, but it can be assumed that Christine was wary of including a picture of herself, being a goat, and instead chose a picture of a human.