What did Rachel Dolezal do to her adopted brother Izaiah?

At the center of the story of Rachel Dolezal are her disagreements with her parents about the rearing of Izaiah, one of the four children they adopted.  This is the boy she told many people was her own son.  Izaiah voluntarily came to live with his oldest sibling when he was 16.

Rachel Dolezal's parents appear to promote the racial harmony model of civil rights that reached its apex in the early 1960s.  Rachel promotes the black nationalism view of civil rights that has become dominant in academia and the media. 

Six children have been identified in news stories.  Their names are straight out of the Old Testament: Rachel, Joshua, Ezra, Izaiah, Esther, and Zechariah.  Four are adopted.  All of the four are black.

According to another of their adopted sons, the parents were not happy with what Rachel was teaching Izaiah:

“Izaiah always was her favorite child,” Ezra Dolezal said. “… She turned Izaiah kind of racist. Told Izaiah all this stuff about white people, made him really racist toward white people.”

Zach Dolezal, the third adopted son, is also critical of his big sister.

“I can understand hairstyles and all that,” Zach Dolezal said of his sister’s alleged attempts to appropriate black culture. “Saying her brother is her son, I don’t understand that.”

Then there were the allegations that she and Izaiah had both been beaten with a whip by their white mother and "stepfather."

The upshot of all this is that Izaiah, who is now 21, appears estranged from his adopted parents and his adopted siblings.  According to his adopted father, Larry Dolezal:

The last we heard he was either attending pre-law at the University of Idaho in Moscow, or through the branch campus in Spokane or in Coeur d’Alene[.]

I feel sorry for the family.  Lawrence Dolezal was employed by Creation Ministries International.  This is an organization that promotes a literal reading of the creation story in the Book of Genesis.  It's not my cup of tea when it comes to doctrine, but by all evidence, the Dolezals are sincere in their beliefs and act upon them.

Adopting children takes a special kind of person, especially when those children are of a different race, as such children can develop identity and rejection issues from an early age.  (I have a close friend whom I can't remember not knowing who raised four Korean children.)  The Dolezals raised their children with Christians of other races and look like a happy family in the photo of their daughter's wedding to a black man.  There is no evidence that anyone in this family harbors any racial animosity.

Except, that is, for Rachel and, according to his siblings, her brother/son Izaiah.  That animosity does not appear to be something either of them learned as children.