It should be noted that Please Don't Eat the Daisies, the book, is a collection of comic essays about Kerr's life as a playwright, housewife, and mother. Isobel Lennart is a piece of fiction that borrows a few details from Kerr. The two properties have very little to do with each other. Your idea about Doris Day in Mary, Mary is very interesting, and I agree she might have made something very amusing out of it. I suppose it was impossible that Barbara Bel Geddes would ever have been cast in the film.