Sora was GOING to say that his sister was the Princess of Balamb, and the only one able to produce the heir to the throne. She's not going anywhere.
He refrained because he didn't think Riku would appreciate it.
"No one is trying to take her away," Sora reasoned. "But yes, you are being adorable and protective."
Walk. Room. Walk. Room. "Walk," he decided. "Sometimes I feel as though I do not get enough physical activity anymore." Like he was always on the throne or in meetings or tired and sitting around his room or eating or something. He hardly ever rode his horse anymore. That displeased him greatly.