It sounds like her son has grown up to hold her values: that a little race deception might help him get ahead. She has raised a child to be a liar who manufactures "victimization" to avoid responsibility, however - her brother and son are still young. Hopefully Rachel will be imprisoned for mail fraud, and they can learn from better people.
I'm impressed with her biological son, actually. He's been taught since birth that his father is a wife and child abuser and that whites are bad, and he's watched his mother repeatedly claim hate crimes against herself AND him, and yet when he's been questioned by the police he has been entirely truthful that he wasn't threatened, worried, or scared.
Her brother? Sounds like he's taken another path, perhaps because RD is his only parental figure. RD's ex shares custody, so maybe his son is around sanity and truth 50% of the time. Maybe, in fact, that's why RD felt the need to manufacture another son, one more likely to fully reflect her own POV.