So a family of mice got into my groom bag and made a nest. What should I do with my brushes and my bag?

DISINFECT! I don't know where you live but mice typically carry lice and other pests. Boil some water and give all your brushes a good soak and remove all the hair in them. Then get rubbing alcohol or metho spirits ( or some disinfectant that is human grade and safe on skin) and soak the brushes in that. Lather them up in the disinfectant then rinse them fully in hot water. There should be as little dirt left in them as possible :)
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