Rilla of Ingleside (1921) is the final book in the Anne of Green Gables series by Lucy Maud Montgomery, but was the sixth of the eight "Anne" novels she wrote. This book draws the focus back onto a single character, Anne and Gilbert's youngest daughter Bertha Marilla "Rilla" Blythe. It has a more serious tone, as it takes place during World War I and the three Blythe boys -- Jem, Walter, and Shirley -- along with Rilla's sweetheart Ken Ford, and playmates Jerry Meredith and Carl Meredith -- end up fighting in Europe with the Canadian Expeditionary Force. (Summary by Wikipedia)