6 year old with a checkbook!

At my 10 year olds soccer game this past weekend, my two younger children were (surprise!) not getting along. I decided I had had enough, and told them that for every time they were rude to each other they owed me a dollar. So my daughter was up to two dollars, when she could not help herself and hurt her brothers feelings again. I said " Oh you are up to three dollars ! " She replied " Oh fine I will just write you a check! " Of course I laughed out loud to that one, and never got the money!