How does Saki use irony in terms of the aunt's take on stories?

"It's a very difficult thing to tell stories that children can both understand and appreciate." (5)

This quote, spoken by the aunt, becomes ironic because it is quickly refuted by the bachelor's story. It is clear from the children's questions and comments that they understand the story, and they praise the bachelor and his story after he finishes. The aunt is proved wrong in her belief about stories for children, perhaps because she would have never thought to tell a story like the bachelor's.