"Tetra is revealed to be a descendant of Princess Zelda in the line of the ancient Hyrulean Royal Family when the King, Daphnes Nohansen Hyrule, gives her the rest of the Triforce. In the final battle, she helps Link defeat Ganondorf by shooting Light Arrows in various manners. At one point in the battle, Ganondorf's hits her and knocks her out for around two minutes. When she regains consciousness, she again helps Link defeat Ganondorf by firing Light Arrows at Link's shield to hit Ganondorf. Shortly after, she and Link embark to find a new land that will be the next Hyrule when ancient Hyrule is flooded. "

This is what the wiki said but i'm sure they are the same person.