Why am I doing this?

Yesterday we began the work of painting Caleb's room. It was what we decided to do to celebrate the end of first grade (in May) and are just getting to now.

After the first coat of paint was put on the walls yesterday, I was helping Caleb sort through his 'stuff' - now piled in the hallway. (He had wisely observed that he had too much stuff - especially when it came time to put stuff away to be moved out into the hallway.)

Anna came up to me in the hallway and asked if she could help.

"Sure, Anna. How about you collect all the tinker toys and put them
in this?"
"Okay!" happy Anna who loves sorting heads off on the tinker toy hunt.
"Mommy, I'm done."
"Okay, Anna, do you want to help some more?"
"Yeah!"
"Okay, would you please go through this pile of papers, and
anything that has anything to do with legos put in this pile?"
"Sure."
Contented Anna sorts papers.
Anna looks up.
"Mommy, why am I doing this?"
"Why are you doing what?"
"Why am I helping Caleb? He is never nice to me and I am being nice to him."
"Well, Anna. That's how Jesus tells us to do it. If someone is mean, we are supposed to be nice in return."
"Mommy?"
"Yes, Anna."
"That's wrong."