Daisy

Did you know that one of Peach' costumes resembles Daisy? To play as Daisy, select Peach at the select screen, and press X/Y button until you get the costume that shows Peach in a yellow costume with a darker skin color. This is simply a costume, and does not affect Peach' play whatsoever.

In addition to this, there is also an Easter Egg with the Daisy Trophy. If you go to the Daisy throphy screen and move the camera behind her head, you can see that she has a third eye!