so confused

In our effort to teach Andrew his colors, we have managed to confuse the heck out of him. He definitely knows blue, but he seems to have a hard time with the rest. He knows yellow most of the time, but as soon as I think he has it down, he'll call a green Lego yellow or a red Lego yellow. Tonight, out of nowhere, Andrew ran up to our red living room wall and with all of the conviction a 21-month old can have, Andrew yelled..."Yellow!" We busted out laughing and yelled Red!!!! back at him.