Although the stars of this movie are known for a lot of comedy, this is a very serious and heartwarming film.<br /><br />Will Martin, (Neil Patrick Harris), is a young man rising up the corporate ladder in New York when he is called home to settle his recently deceased grandfather's estate. The grandfather owned a real estate business and now it belongs to Will. Will's parents were killed in an auto accident when he was a child and he was raised by his grandparents. Ruth, (Debbie Reynolds), is Will Martin's grandmother. Julia, (Alexandra Wilson), is a young divorcée with a son about 10 years old. Miss Enid Cook, (Beverly Archer of Mama's Family), is an accountant in the real estate company.<br /><br />Ruth surprises Will with his grandfather's diary, which she only discovered after his death. It is mostly the mundane stuff of day to day life. The big surprise to Ruth and Will is the grandfather's frequent references to a mysterious female named Lillian. Will promises his grandmother that he will discover the truth about Lillian by Christmas Day. Both greatly loved the grandfather and give him the benefit of the doubt - up to a point. The nagging mystery is troubling. Will begins a search via old photos, old friends and employees of the real estate business. It leads Will to learn a lot about himself, as well as his grandfather.<br /><br />The movie includes side plots of problems for the Alexandra Wilson and Beverly Archer characters.<br /><br />No spoiler here. Trust that all mysteries are resolved to the satisfaction of all concerned, not least the viewer. The Christmas Wish has a pip ending. Some might consider it slightly schmaltzy. If so, it is very high quality schmaltz. I was engrossed from beginning to end. Get out your handkerchiefs.