My Theory is that Blair and Ashyln are actually half sister of the other ten and King Randolph's step daughters. King Randolph is a very kind man, and takes care of them still even though his wife is gone, and loves them just as much as his blood daughters. In fact they were the first kids he was around when he was married so he probably has a close bond with them. So technically, Courtney would be the heir to the throne, but King Randolph considers Ashlyn one of his own, so that is why he lets her be the heir. The theory that they are step sisters is based on how they are the most different looking. All girls have a peachy or light tan skin tone. Ashlyn has soft brown skin and Blair is very pale. You can really take notice with Ashyln's doll.

Her doll has an obvious brown skin tone, and an African-American shaped nose. She appears to half black, even in the McDonald's doll too.

And while this may seem more apparent in the doll, you can see it in the movie a bit, it's more noticeable with this side by side comparison.

All other sisters except for Ashlyn and Blair have Genevieve's skin tone. She gets her brown hair from her mother and her father was probably mostly black and so she is biracial.

Blair is the only girl with black hair, and she is extremely pale. You can really notice how pale she is when she is wearing a nightgown.

She is the palest of all the girls. This is a comparison of her and another sister.

I think she is half Asian and also biracial like Ashlyn. You can see in her doll that her eyes are narrow and almond shaped, it looks like an asian face sculp.

Her father was probably Asian and after Blair was born, the queen and King Randolph married not too long later. Ashlyn is over 20 years old so it would make sense that the Queen hadn't been married by then.