I sometimes wonder why the water in the water bowl gets dirty so fast. Sometimes you will even see some fur floating in the water. I changed it, and 2 hours later it is dirty again. Last weekend, I finally caught the culprit!
Right after I changed the water in the water bowl, I caught Sesame putting his paw in the water bowl, took it out, licked it, and then put it back again! He then used this paw to dip into the water a few times, all this time looking at the water, probably fascinated by the movement and reflection. I wonder if he learnt this from the mother also, but I have not seen Pepper does this before.