Mariemaia Kushrenada
This sinister child is the biological daughter of Leia Barton and Treize Khushrenada, who at the time of his death was the leader of the short-lived World Nation. Thus, Mariemaia has a claim to rulership of all humanity, and she declares war against the Earth Sphere Unified Nation in an attempted coup d'etat. Her claim is backed up by the forces of the Mariemaia Army, whose mobile suit legions are unopposed by the disarmed government.
Though Mariemaia is one of the creepiest and cruelest seven-year-olds you're ever likely to meet, she's nonetheless an unfortunate, even pathetic, character. Her mother died when she was two, and since then she's been raised by her power-mad relatives as a figurehead ruler to legitimize their attempt at world domination. Only too late does she realize how unimportant she is to her grandfather's plans, and how little love her blood relatives have for her.