Please explain the irony in the story.

The plot of the story is grounded in situational irony, a
conflict between ordinary folks on the one hand, and both chance and evil on the other.
The forces of chance are built up by an almost overwhelming set of coincidences that
lead in a straight line to disaster. These are:a. the decision to go to Florida,b. the
decision of the grandmother to go too even thoughshe says at first that she will stay
home,c. her hiding the cat in the car because she doesn’t wantto leave it behind,d. her
remembering the house she wanted to see, and excitingthe children by making up a “secret
panel” (paragraph 45),e. her realization of her error just at the wrong moment,f. her
upsetting the basket with the cat in it,g. the cat’s jumping on Bailey’s neck, thereby
causingthe wreck that makes the family vulnerable, andh. the Misfit’s being nearby when
the accident occurs.