On pg. 5 it says "Gram and Gramps wanted to see Momma, who was resting peacefully in Lewiston, Idaho." The narrator suggests that Momma is 'resting'. This foreshadows that the mother is dead which you find out about on pg. 267 it says "on a little hill overlooking the river and the valley, was my mother's grave."
When Mrs. Winterbottom goes to visit her long lost son, it becomes obvious, then, that Mr. Winterbottom misses her. It is only after something is gone that you realize you truly loved it. This happens again many times throughout the novel.