I Need Go Potty!

Yesterday I was helping Meredith get her Blue's Clues video set up to watch while I got the triplets down for their nap. When I came back into the playroom, Amanda was sitting on the floor and had taken off her socks and pants, and was working very diligently at taking off her shirt. When I asked her what she was doing she replied, "I need go potty!" I finally convinced her to keep her shirt on. She sat on the little potty for about five minutes but nothing happened... How in the world am I going to potty train three of them???