The Little Card is very difficult to capture because of it's size and powers. It has the ability to shrink whatever it touches, or whatever touches it. The only way to revert back is to touch it a second time. Sakura faced this problem before being able to seal it.
In Episode 24, Sakura discovered this cards form in her house. Before sealing however, it attacked her and she shrank. After a long ordeal and after saving Madison from it, Kero aided Sakura in grabbing Little, thus letting her return to her normal size. When used as a card, it has the sbility to shrink anything down to a much smaller size.
