The Once and Future Heir

Alexandria Pendragon is the rightful heir the the throne of Camelot. Merlin took her away the night she was born, disguised as the great wizard Emrys to train her to be the most powerful High Priestess. Merlin isn't afraid to teach Alexandria, or Alex, even after what happened to Morgana. He knows that Alex will only use magic for good, so at the age of 15 he sends her to live with Gaius as assistant to court physician.
She has no idea that she is Arthur and Gwens daughter until Merlin decides to return back to the castle after being missing for 17 years.

Working her way up to becoming Queen Guineveres personal servant, she finds out what really happened that night, 15 years ago. Once she knows her true identity, she gains a little brother named Felix and the mother and father she's never had.

After a scary ordeal, Merlin tells Alex that she needs to fulfill his destiny of protecting Arthur who has no idea that she possess magic. After Arthur and Gwens death, Alex takes the throne. Is she really up to the challenge of becoming queen?