How did Vera trick Mr Nuttel in the short story the open window by Saki?

In the short story "The Open Window" by Saki, Vera tricks Mr. Nuttel by telling him a fictitious story about her aunt's tragic loss of her husband and two brothers through a window that remained open. Vera creates an elaborate tale to make Mr. Nuttel believe that the figures he sees approaching the house are actually ghosts of the deceased men, causing him to panic and flee. However, it is later revealed that the story was entirely fabricated by Vera for her own amusement.