We have been listening to Christmas songs in the car pretty much nonstop for the last week or two. Yesterday, while on our way home from dance class, Elisabeth asks me to turn it off. When I asked if she was tired of all the Christmas music she said, "Yeah..." A bit later, seemingly in response to the silence, she starts singing her own song. (Sorry for the poor videography, but I was driving and couldn't see where the camera was pointed. The sound is what matters anyway.)
The car seems to be a creative space for my kids when it comes to music. Jonah has crafted a number of songs in the car also, including this one.