Human. Everybody is a mix to a certain degree if you go back far enough. Despite what some like to believe, there is no such thing as a "pure breed" human.
If you really want to use a term that highlights her diversity, I would go for mixed ethnicity or mixed origin or something like that. Do not use race first of all because the concept itself is not very useful and second because terms involving race tend to be laden with racist connotations. I am a mix of 5 different nationalities and I call myself a European bastard but I would not recommend that term.
It is unlikely that you will find a non-offensive single term for this since most people who feel the need to point out a person's 'racial' diversity tend to do so for discriminatory reasons. I am not saying that you are, it is just a quirk of the language's history that most such terms come from a very racist era. There used to be an incredibly nuanced vocabulary for people of various mixes of white and black for example: mulatto, quadroon, octoroon etc.
Anyway if you really, really want to use a term involving race, go for mixed-race or multiracial.