B and A...and C

Lizzy, as we drove away from daycare: "Mom, we were so super good for Donna today."
Me: "That's great. What did you do that was so super good?"
Lizzy: "Well, two things. First, B: we cleaned up the toy room. And then A, we helped with lunch. But then C you ruined it."
Me: "How did I ruin it?"
Lizzy: "We had just gone outside to play, and then boom... you showed up."