Princesses in the animal kingdom can be tricky to identify, but Faline is a pretty clear-cut case. Bambi is the young prince of the forest. Faline is his mate. Conclusion: princess.
Unfortunately for Faline, she and her fellow animals princesses can never wear beautiful clothes, which seems to be a requirement for official Disney princesses.
Being the daughter of a chief doesn't make Tiger Lily a princess, but 'Peter Pan' isn't known for its accurate depiction of Native Americans.
In addition to good fashion sense, Disney princesses are supposed to have personal strengths that little girls can emulate. Tiger Lily is certainly brave, refusing to tell Captain Hook the location of Peter Pan's hideout even when her own life is at stake. But she never speaks and her role in the film is mainly being rescued by Peter and flirting with him afterwards.
"Princess" is a rather fuzzy term for Disney. Just look at official Disney princess Mulan, who has no family connection to royalty whatsoever. Maid Marian isn't the daughter of a King or other powerful figure, but she's a king's niece and that's close enough. Also, she's a fox (literally) and the king's a lion. Try not to think about it too hard.
Maid Marian wears more clothes than most of her fellow animal princesses. But a fox head on a Barbie doll is a creepy prospect that keeps her from going to the big leagues.
'The Black Cauldron'
Most of the princesses Disney has chosen to forget about come from films that were not financially successful, an understatement in the case of 'The Black Cauldron.' Eilonwy had the double misfortune of starring in a massive flop and being a major downgrade of the strong-willed character from the book on which the film is based. Eilonwy just doesn't have much to do and the fact that she's a princess is only barely mentioned.
Is Nala a princess? Simba doesn't get called a prince much, but he is Mufasa's son and the future king. Nala is his betrothed and, according to some theories floating around the internet, might be Mufasa's daughter. Either way, she has the "related to royalty" part down.
If being a Disney princess is about being a good role model for little girls, then Nala has a lot in her favor. She's strong enough to take down Simba, ventures out on her own to find help for her pride and calls Simba out for ignoring his responsibilities.
Unfortunately, lions make lousy fashion dolls, so we're unlikely to see a coronation for Nala anytime soon.
One acceptable way to become a Disney princess is to marry a Disney prince. Megara's main squeeze is the son of Greek gods, so he's definitely got parents with some serious power.
Megara is unique among Disney heroines because she's not merely disinterested in love, but actively opposed to the idea thanks to a bad relationship that literally cost Meg her soul. That could've been very interesting for a Disney princess, but 'Hercules' had mixed success in theaters, so Meg never made the cut.
Princess Atta and Princess Dot
'A Bug's Life'
If Merida counts as a Disney princess, so should the two daughters of the ant queen from Pixar's 'A Bug's Life.' Dot is adorable, plucky and as close to a real little girl as an ant can get. Atta is her older sister, a soon-to-be-queen who actually has some royal responsibilities, a rare thing for a Disney princess. Neither of them are fashion plates, but they're both strong characters capable of holding their own against a hoard of grasshoppers.
'Atlantis: The Lost Empire'
Unlike most Disney princesses, Kida is a formidable warrior. She is the daughter of the King of Atlantis and actually becomes the queen by the movie's end, another rarity for a Disney princess.
Kida's chances of ever being an official Disney princess are hindered by the poor performance of her movie and the lack of Atlanteans interested in buying Disney merchandise.
Giselle is the only Disney princess to start out as an animated character and then transition over to live action in her movie. 'Enchanted' parodies many of the Disney princess tropes and Giselle herself is as sweet, kind and naive as Cinderella, Snow White and the rest.
Giselle almost ended up being an official Disney princess. But her most unique quality turned out to be her downfall -- making Giselle part of the Disney princess brand would require securing lifelong likeness rights from actress Amy Adams. Animated Disney princesses never have such problems.
Vanellope von Schweetz
It's not revealed until the end of the movie, but pint-sized racer Vanellope is actually the princess of the video game Sugar Rush. She even gets a suitable princess gown, but promptly trades it in for her usual hooded sweatshirt and black skirt. She's also far younger than the average Disney princess, most of whom are teenagers whom young girls can aspire to be like someday. Who knows, maybe an older Vanellope will appear in a 'Wreck-It Ralph' sequel and become eligible for official Disney princess status.