A convincing character is more than a list of personality traits. Audiences understand character through choices under pressure, relationships, habits, contradictions, and the pursuit of what matters.
The core idea
Identify script facts: where the scene occurs, what has happened, what each character knows, and what is at stake. Keep those facts separate from imagined backstory.
How to apply it
Ask what the character wants from the other person. Use an active verb such as persuade, reassure, challenge, hide, or buy time. Let the relationship and obstacle influence how the character pursues that goal.
Try this next
Write one sentence for the objective, one for the obstacle, and one for what changes by the end. Perform the scene, then adjust the tactic while keeping the objective.