No matter how often Disney movies begin with a dead mother , they rarely dwell on grief. Pixar movies, on the other hand, have always trafficked in melancholy. They often explore the many facets of loss. They’re funny-sorrowful, melodies in a minor key, tonally Jewish. And this season’s installment is the most mournfully engaging yet. Just look at the dolorous history of Pixar films: The Toy Story trilogy is about how we humans can never truly know those we love; it ponders the losses we incur simply by growing up. Finding Nemo and Finding Dory look at parents’ fears of losing a child, and concerns about raising a child with a disability. Ratatouille is about all the Proustian associations we have with food—how transporting a taste can be, how tied into golden-toned, long-in-the-past memories. Brave is about mothers and daughters and the necessary pain of growing apart. Inside Out is about coming to accept ...