Two young Kings: Martin Luther King Jr. and his younger brother, A.D. King in a 1930s era photo. The brothers grew up in a religious family, led by their pastor father, Martin Luther King Sr., who expected great things from both of them. But while King Jr. followed the path, A.D. King delayed his college education and entry into the ministry while he raised a family. King biographer and Stanford University historian Clayborne Carson, said that while Martin had his own disagreements with the sometimes domineering Daddy King, he was always careful not to damage the relationship. 'A.D. would cross the line,' Carson said. 'Martin was always his father's favorite son. He was older, he did well and he fulfilled his father s ambition. From what I understand about (A.D.), he had internal demons.'