The first four were painted without a camera present to confirm or deny her actual input whereas, the bottom one, "Ocean" was the one painted whilst being videod. Quite clearly a childlike use of color and shape. (Note the adorable yellow teddy bear.) And the top four have obviously had more thought and consideration put to them. For example the colour choice and the brush work is much more deliberate, it's been thought about. (Not that I'm saying I like these pieces or think they are very good.) These examples include my personal favourite, "Eyes"(3rd from the top), which features a face in it's top right corner, complete with proportional features. "Four years old you say? Never..."
I don't think it really needs to be said but, they're obviously the work of an adult or at most a child with adult direction, which to be honest you could probably make a lot of children do, if you make them. What makes me laugh the most is that people buy these things for ridiculous amounts of money thinking they are the work of some genius. Yeah, her father who is laughing all the way to the bank. The couple who bought "Ocean" only bought it cause it was the one in the video, because it is more famous. She quite clearly didn't like it, but paid $20,000 for it. What an idiot.