Joan's expression becomes a little sad. "Sherlock spent most of his life pushing people away," she says softly, still gently stroking his hair. "His father kicked his mother out of the house and sent Sherlock and Mycroft to a boarding school. You can imagine how a young, brilliant, eccentric kid like Sherlock was treated by the other boys. Then his mother died. I think for a long time he kept emotional distance from everyone to protect himself. Then he fell for 'Irene,' and it almost killed him."