This is the second appearance of the book "Where'd You Go, Bernadette" by Maria Semple (though the first chronologically). The first appearance was in Chapter Thirty-Seven (2016) in which Jane interrupted Patricia's book club in their discussion of the same book.
Not the first time Brett Dier had his mom played by Molly Hagan. In the anthology series, of Fear Itself, in the Skin And Bones episode, she also played Dier's mom.