Poop in the tub

I let Troy take a bath in a plastic tub that we have before he went to bed tonight. He was in the bathroom by himself for a short while. I kept talking to him the entire time, and I asked if he wanted me in there with him. No, go away!! Ok, that made me a bit worried, so of course I had to go and take a peek. There he is, sitting in the tub playing with something I at first don't recognize. He looks up at me and smile and says: poop in my bathtub. Yikes!