Paul is greatly influenced by his materialistic mother who measures personal worth by someone's "luck" and monetary success; moreover, she is incapable of loving her children as she feels that they are a "burden thrust upon her." When she is with her children she feels the "centre of her heart go hard" and senses that her children detect this fault; so, she becomes anxious and more gentle about them. Others perceive her as a tender, loving mother, but her children know she is not.
In truth, Paul's mother is selfishly only interested in social prestige and material possessions. But, because it is only natural that a child desires love from his mother, Paul tries to satisfy her desire for money, hoping that she will then love him and his sisters. The hyper-sensitive Paul detects "an anxiety in the house" as there is always the "grinding sense" of the lack of money for his mother to live as she would like. When his mother equates their insufficient finances with the lack of luck on the part of their father, Paul asks her, "Is luck money, Mother?" she replies that luck is what causes you to have money. It is this remark that his mother makes which drives Paul to become lucky so that his mother will have more money.
One day when Paul speaks with his Uncle Oscar, he reveals the reason he has been riding his rocking horse in order to predict the horses who will win the races. He tells his uncle that he hates the house for whispering.
"What does it whisper?"
"Why--why--the boy fidgeted--"why, I don't know. But it's always short of money, you know, uncle."
"I know it, son, I know it."
...."And then the house whispers, like people laughing at you behind your back. It's awful, that is! I though if I were lucky_______"
"You might stop it," added the uncle.
Paul becomes obsessive in his desire to make his mother happy because when she receives money "mysteriously" from Paul, she spends it and more as she can never be satisfied in her materialistic desires. Finally, the poor boy succumbs to his feverish trances, and although she has made some efforts to curtail Paul after discovering his obsession, it is too late for the mother to give him the love that he has always desired.