She is a Princess because she is the daughter of Prince Andrew the second son and third child of Queen Elizabeth II and Prince Phillip
Princess Beatrice is the eldest
The prince Beatrice is the daughter of the Prince Andrew of York And Sarah, duchess of york (The United Kingdom)
The princesses are:MikotoTouruYuujirou
Princess Royal who is currently princess Anne, the daughter of HM Queen Elizabeth II, is the aunt of Princess Beatrice of York!