Topic: POV character's "view" of others
I have a POV character named Joseph who is together with his mother, Mary, who is the royal regent of the planet New Bethlehem. Normally, Joseph thinks of her primarily as his mother, not Mary or regent. However, in the middle of an attempted coup, Joseph's mother is very active in the scene (she gives orders, acts, reacts, etc.). I can't keep calling her "Joseph's mother" as it becomes very repetitive in the scene, even within individual paragraphs. Is there any reason I should avoid calling her Mary or regent as well, thereby reducing the repetitiveness? I find this issue comes up frequently, and I'm often told to choose one way that the POV character thinks about someone and stick with it.
I'm curious how others handle this in their own writing.