At the end of Chapter 4-4, there is a golden statue of Squirpina XIV. When the heroes see the statue, Squirps tells them who he really is and reveals the story of his mother. 1,500 years ago, Squirpina had, by an unknown means, became aware of the imminent destruction of the world Count Bleck would try at years in the future and realized that only the Pure Hearts could be able to save the universes from this destruction. Thankfully, she had a Pure Heart and decided to hide it at the end of the Whoa Zone, locking her son in a hibernation capsule and giving him the mission of leading the heroes prophesied in the Light Prognosticus to the Heart after they awoke him.
Squirps was, in the end, successful with the mission and gave Mario and friends the Pure Heart. Afterward, he fell asleep (and was assumed dead until the heroes returned to Outer Space later and found him alive) in front of the statue of Squirpina XIV and softly asked his mother if she was proud of him. Squirpina herself never directly appeared, however, and the fact that 1,500 years passed before her life and the setting of Super Paper Mario renders it is likely that she is dead.