Grouping the characters in PAX (by chapter 6)

We are reading the book Pax. Right now we are in chapter 6. These are the characters we have come across.

Main Characters:

Peter

Pax

Secondary Characters:

Dad

Grandpa

Bristle

Runt

 

I would put it in this order because the main characters Pax and Peter show up mainly in the story and they basically make the story. The secondary characters go along with the story so they make the story go along.