In "Princess September," how has Maugham shown that jealousy can reach extreme heights leading to the suffering of others?

In the story "Princess September," jealousy can be found within the title character's sisters.  Because the princess of Siam, named Princess September, was the last daughter to be born, she was not subject to having her name changed again and again.  First, the king of Siam named the daughters (when he had only two) after day and night.  Next, the king renamed them after the seasons (when he had four).  Third, the king renamed them after the days of the week (when he had seven).  Finally, the king was in the middle of renaming all of them after the months of the year when Princess September was born.  The remaining children were boys; therefore, the king ceased the naming escapade.  All of these name changes caused the older princesses to be jealous of Princess September.  In fact, when Princess September receives a beautiful bird as a gift, the sisters convince her to lock the bird in a cage.  Before being caged, the bird gave Princess September much happiness.  The sisters wanted to take away that happiness due to their jealousy; therefore, they "suggested" caging the bird.  Of course, as soon as the bird was caged, it stopped singing and interacting with Princess September.  Princess September became so distressed that she set the bird free.  Thus, you can see how the sisters' jealousy led directly to Princess September's unhappiness.