Asia and the potty

Asia went potty in the potty chair! This happened last week. I didn't even know she went. Zach was sitting on the toilet before his bath, so I put Asia on the potty chair and told her to do what her brother was doing. That's a little tough during times when he's standing up to go potty. She's tried that before and doesn't understand why she can't always go the way Zach goes. And Zach will ask the same thing - I go potty standing up, why can't Asia? Or he'll sit on the toilet and say, "Now I'm going pee pee and poo poo just like Asia - sitting down!" The other day in the bath, Asia was putting soap on Zach, patting him on the back. Eventually, she was playing with his "wee wee" wondering what it was. Oh the joy of explaining the human anatomy to a 2 or 4 year old.
So anyway, back to the potty thing. Zach got into the bathtub first. Then when I picked up Asia to put her in the potty, there it was! A little bit of pee! And she did it again the next day, but in the big toilet with a different kind of potty chair on top of it.