My higher self says, "Wow, I'm so terribly sorry that you, your child and the au pair were unable to work through your situation. No child ever deserves to be kicked. No adult ever deserves to be kicked. Clearly, she must go. Clearly, the children will be better served by some other person."
My middle self says, "What the heck is wrong with your children? Do they have no boundaries? Has anyone ever taught them to behave like civilised creatures? Kicking results in sitting on the naughty stair. And the same applies to au pair. "
My lower self says, "Clearly, your children picked up on your vibe that you thought she was inferior. Clearly, they choose to act upon their race privilege. Given that the historical pacifist responses to colour aroused behaviour are passe, incorrect and untenable - the au pair had a temporary moment of realistic human emotion. It is unfortunate she responded as she did. She should have kept her cool and reported your family to a child protection agency...we all know abuse is a learned behaviour.
Furthermore, we know when people are looking down our noses at us. We have adapted to treating the surreal as real. From time to time, we forget that we have to be kind, rigorously subdued and controlled beyond normal reason when faced with such as the likes of you and your children.
My higher self says, "I wish all of you peace. I hope everyone involved has an opportunity to reflect, grow and evolve. All things happen for a reason. Perhaps there is a blessing in here for everyone."