How does vera’s fanciful flashback have ironic consequences

In "The open window", Mr. Nuttle moves to the countryside to relax, as a recommendation of several doctors. There he visits some old acquaintances of his sister. The niece of one of them, Vera, tells him that her aunt's husband and kids have disappeared, so when Mr. Nuttle sees them arriving across the field, he thinks he is seeing ghosts and fleeds. This is ironic because it does nothing to help his nerves.  

the answer is both an appeal to ethos and logos (if that's what your question options were)

there purpose is to entertain