Eilonwy is not included the Official Disney Princess line-up or in any of the merchandise. This is most likely due to the film's poor performance at the box office.  Princess Eilonwy has been nicknamed by fans as the "Forgotten Disney Princess" because of her little-known status. Princess Eilonwy deserves to become part of the other princess's like Belle, Tiana, Odette, Snow White, Ariel, etc. Even though the "Black Cauldron" didn’t receive a high performance at the Box office, it was still a good childhood movie, and Eilonwy is a Disney Princess. Despite its lack of success in the theaters, there has been a recent influx of older generation fans that love her, and are trying to revive her for newer generations on DeviantArt, Tumblr, and other social sites. I am asking people who have watched or read about her in the books (the novels of The Chronicles of Prydain). She’s just like any girl, and relates to those other Princesses like Snow White, Belle, and Princess Odette from The Swan Princess; she has such similarities with Princess Odette. They are raised the same way, gets captured and she [Eilonwy] escapes from the Horned King's castle. I think this petition can make a difference because there is a lot of new princesses coming to Disney, some that you wouldn’t think are true Disney Princesses. Eilonwy has made her debut in 1985, while others have just officially been introduced. I feel that Princess Eilonwy of Llyr from The Black Cauldron deserves to be officially announced as a “Official Disney Princess,” Please make this Dream a Reality, give back to this girl and make her one of the Princess Girls.

http://www.youtube.com/watch?v=mB0uJTMf1kQ

 http://syfa10.com/play.php?movie=0088814