Why did Alice call her daughter?

Because in the game story, Alice is the princess of the royal camp. According to official website's query of Blue Route, in the game Blue Route, Alice is the role of the royal camp, and she is the mother of the flagship Royal Ark of the Royal Fleet. She is called "daughter" because in the game plot, Alice is the princess of the royal camp, her father is the former captain of the royal ark, and her mother is one of the leaders of the royal camp. Therefore, she is regarded as the princess of the royal camp, also known as the "daughter".