Bi-racial here. I identify as AA. Most AA's with an actual AA parent will identify as black and probably have AA cultural markers (history in America, AA family, black church experiences, black social circles, AA traditions, black music, code switching and dropping the r's at the end of words, understanding of the legacy of the "one drop rule.")
I think bi-racial children with a black mother will identify as black. Bi-racial children with a non-Black mother, not so much. At least among people I have known.
@Anonymous PP. I have a white mother. So does Mariah. I will say though, my mother is/was an exception in her child rearing style. Black/Bi-racials who are raised without any connection to their black side tend to have problematic identity issues from my experience.
Op: maybe thats what she’s experiencing - identity issues? She certainly doesn’t look racially ambiguous to me.
The lesson here is that you should never assume a person’s race just by looking at them