Chores

The boys have chores they have to do everyday (things like cleaning their rooms, taking care of their animals, setting the table, etc.). I went into the kitchen a few minutes ago and Caleb was washing their cups from snack. He was pouring soap into the cup and then using a dish rag to clean them. He said he wanted to surprise me by doing a chore he was not told to do. Then he smiles and says "I may be small, but I can still clean good!"

Is it unfair to use that against him when he does not want to clean?