This passage gives the impression that Finch’s family isn’t particularly close-knit or at home much, as they all seem busy and preoccupied with their own lives. As Finch describes his family and who’s the “mistake” of his siblings, he shows that he defines a “mistake” differently than perhaps Decca and Kate do. While his sisters think of Decca as being a mistake because she wasn’t planned, Finch suggests that
he’s the real mistake, perhaps because of how he views his mental health issues.