I am a novice working on a historical novel with four viewpoint characters. Three of them will be involved in subplots connected to the main plot, and each character will have a character arc and will undergo change. The fourth will be the title character and "main" protagonist and and will be given correspondingly more space.
I am undecided about giving a fifth secondary character POV status, namely the grandfather of the protagonist who will appear in only one or two chapters. This character has deep convictions and his life experiences have great meaning to the overall theme and so I would like to give him his own viewpoint, but I already have four POVs!
My question is: How can I give a sense of this character's lifetime of suffering and disappointment without giving him his own POV? Is there some kind of technique? Is it possible to write something like the following about him?
*John was aware of what imprisonment can do to a man. He had felt the agony himself and had seen its effects on others. The experience had changed him. He was no longer the bright young lad his father had once admired; the favored son who would conquer the world. The world had conquered him. *(Not actual text)**
In other words, I am concerned about the diluted effect of having too many POVs for a 300-page book but I would still like to make this particular character's story important and meaningful. Is it possible to do that effectively through have description rather than quoting the character's own thoughts and feelings?