Catrina

Lady Catrina was a noble of the House of Tregor and friend of Gaius. As a child, she was treated by him because she had an incurable bone disease that made it difficult for her to walk. Apparently she met the Pendragon family at some point during her life.

Later a female troll assumed her appearance and managed to enter Camelot's court and became Queen of Camelot by placing Uther under a spell. It was said that the real Lady Catrina was the last survivor of the House of Tregor. The troll stole the badge of her family to enter Camelot, but didn't know about her bone disease. This was a fatal mistake for the troll, as her deception was uncovered by Gaius and Merlin before she was finally killed by Arthur. It is unknown whether the real Lady Catrina is still alive and living somewhere else, or if she passed away at some point. According to Gaius, Catrina was a kind and gracious woman.

Trivia

 * Although Catrina's appearance appears in the series, she, most likely, died, as the troll freely used her seal and appearance, without fear of the appearance of the real Catrina. It is possible that after the House of Tregor's fall, Catrina was hit and died in the hands of the troll, thanks to which he received her seal and appearance.

Gallery
Catrina de Trégor