Kamala Harris’ father, her only living parent, was not in the audience with the rest of the vice president’s relatives during the most important speech of her political career Thursday night. Donald Harris, a leftist economist who turned 86 Friday, was conspicuously absent from the row of family that included husband Doug Emhoff and his two adult children, Cole and Ella, as well as Harris’ younger sister, Maya Harris, and her family at the United Center in Chicago. While Harris spoke lovingly of her mother’s influence on her life in her speech accepting the Democratic presidential nomination, she only fleetingly...