"You know Regulus went to therapy." Their eyes shot to him, surprised. "He didn’t want you to think less of him, so he never told you. I know your parents never believed in any of that." Sirius remembered a doctor once telling their parents that Sirius might have ADHD. They tried to sue him for malpractice because they believed that ADHD was invented in order to "drug and control the masses’ (similarly to what they believed about vaccines). 