Your help needed

A question for people who are familiar with one-year-olds:

Would it be possible for a bright 14-month-old who has advanced verbal skills to insist on a particular Halloween costume, before said costume was purchased?


(This may or may not have something to do with a teeny tiny ficlet.)

Second question: Add an illness/injury component so as to be able to submit this for a paricular challenge, or not? Keep in mind I don't have a plot so much as an idea.