What two mistakes does Aiden make in his role as Regan's protector in the novel, Murder List?

Regan's oldest brother, Aiden, who took on the role of her protector when she was a teenager is unable to let go of the role now that they are both adults. Two mistakes that Aiden makes include Aiden buying her a new car (not letting her buy and choose her own), and then leaving her out of a family meeting.