Writing on Disney Stationery: Infringement?

Dear Rich: I sell non-Disney tiaras on Craigslist and when I gifted one to my niece I decided to use some of my Disney princess stationary to also write her a letter from a "princess" so she would think the tiara was sent from one of the princesses. I sell the tiaras for $10 if I added a letter to every purchase (if requested) with no extra charge is this a Disney violation? Hey everybody, it's Disney time (Boogety, boogety, boogety shoo!) We get so many Disney letters, the Dear Rich Staff sometimes thinks about a subblog just dealing with the Magic Kingdom. but then we get depressed thinking how sad that we spent all that money on law school and Kaplan courses (not to mention those dopey  payments to the American Bar Association so that we can keep our dopey ABE life insurance) and for what? To tell people whether they can dress like Daffy at the company Christmas party?
Right, you had a question. We like the idea of using the letter and tiara combination. (It's that same kind of personalized gift approach that set Xavier Roberts apart when he created those lovable Little People nee Cabbage Patch Dolls with their adoption papers.) You say that the purpose of your letter is to make the recipient "think the tiara was sent from one of the princesses." Question: Do you need Disney stationery to make the recipient think that thought? If you do, then it seems as if you're really trying to make the letter-getter think it's from Disney Princess Headquarters. Once you imply that Disney is somehow associated with or endorsing the tiara, then you move into a troublesome legal area in which Disney could claim what you're doing trades off their name or falsely advertises their products. That's not to say you can't use Disney stationary to send out gift tiaras. It is stationery, after all. But -- and this is assuming Disney ever finds out about your use and/or cares -- if the use of the stationery is part of your long-term business model you might someday get hassled.