Lying can be seen as an adaptive way for a child to get what they want that can develop into an adult personality known as The Liar.
Liars live in fear of being exposed. One moment of truth can unravel a lifetime of lies because all of their achievements become suspect. If they lied about something like this, what else did they lie about?
If your manuscript lacks drama, throw a Liar in the story and see what happens.
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