Who is a minor character in Black Beauty and why is (s)he in the story?

More than any single work of its time, Anna Sewell's
Black Beauty effected the humane treatment of horses and other
animals, as well. With the narrative set in a time when horses were the means of
transportation, little consideration of their feelings was often the case as men simply
wanted to have them carry the heaviest loads they could and travel as fast as they could
so that money could be made.  The wealthy class, who had carriages, oten bought horses
for show; therefore, if these horses became marred or "defective" in any way, they were
sold with no regard to their future treatment. Also, in their vanity, the owners of
magnificent carriages often used inhuman measures to make the horses appear equally
magnificent.

For instance, in Chapter 8 Ginger, a minor
character and the stablemate of the narrator, tells Black Beauty that with her previous
owner she was made to wear a bearing rein and two sharp bits, both very painful devices
as the bits cut into her mouth and the bearing rein forced her to hold her head high
constantly. Later in the novel, also, Ginger is victimized as she dies from pulling a
heavy load.  Her poignant history is one that led to action for the humane treatment of
horses.