A writer develops a secondary character based on patients he worked with in a previous day job. He has terrific authentic details, having spent so much time with one particular patient with special needs. The character (who is the protagonist's brother) is of great emotional importance to the protagonist. (The writer is writing what has long been espoused as a good practice for writers ~~ write what you know.)
The writer's front story (dramatic action plot) centers around drugs and money laundering and shady operations, guns and prison and betrayal. His writing strength appears to be developing dramatic action. When asked who his audience is, the writer has not yet considered such. The front story is high-stakes, exciting intrigue, which often resonates with male readers. Yet the protagonist is a woman. She is a "ballsy" woman to be sure, confident and fearless.
When asked how much of his story he wants to involve the other two plot lines ~~ character emotional development (which, at this point, is little, if at all, developed) and thematic significance, again he had no answers. Same reaction in response to whether he plans to include a romantic secondary plot line in his story.
I did not present these questions to baffle him or slow him down. I presented these questions to support him in broadening his scope of what he is doing both in his story and in his life as a writer...
He introduced and developed the secondary character in order to bring heart to the protagonist's character and thus, develop her character emotional development plot. Yet, because he is writing what he knows about patients with special needs, he concentrated on describing the secondary character's behavior without tying those elements directly to the protagonist or give the reader a sense of the impact those behaviors have on the protagonist and even more importantly, how those behaviors influenced the protagonist's backstory development.
Because the secondary character having special needs does not play into the dramatic action plot (in other words, such afflictions are not necessary for the development of the primary plot), I suggest that rather than devote so much time to the development of the secondary character, use his afflictions to deepen the readers understanding and appreciation of the protagonist instead. Her backstory wound of being ignored by her parents in favor of attending to the brother's special needs, bleeds into her everyday life in undercover as she is betrayed by not only the bad guys but the good guys, too.
For more support about the role of Secondary Characters in novels, memoirs, and screenplays:
1) Check out Chapter 6 of:The Plot Whisperer: Secrets of Story Structure Any Writer Can Master (Now also sold as a Kindle edition)
Blockbuster Plots for Writers
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