Denis Diderot said, “Man will never be free until the last king is strangled with the entrails of the last priest.”
Once upon a time we Americans staged a revolution against the Crown. Yet over the years we have retained the idea of royalty through inherited wealth and class.
This leads to some stupid thinking and expectations. One of the stupidest is that we expect the siblings and children of wonderful leaders and great humanitarians to inherit those or share those same traits.
Thus we are surprised when a child of Martin Luther King Jr. turned out to be a bigoted asshole and Bible thumping Christo-Fascist like Alveda King.
The is monkey brain thinking. Good politics, a desire for social justice, the humanitarian instinct are sentiments one learns. Fundie Churches of any stripe do not teach those values. Instead they teach dogmatic hatred and bigotry.
The only reason for giving Alveda King any greater credibility than Porno Pig Pete LaBarbara is the fact she is related to MLK. That is a piss poor reason to give anyone credibility.
People earn credibility, it is not genetic.