The Solar Brace is worn by Ephraim throughout the proceedings of the game, and can be acquired as a physical item at the end of Chapter 16 to promote him into a Great Lord.

Who does Ephraim marry Fire Emblem?

When one sibling takes the throne, the other does not take the title of queen/king. They remain a prince/princess. However, Eirika is being referred to as the queen of Renais. This implies that she married Ephraim.

Are Ephraim and Eirika siblings?

Eirika (Erika in the Italian version) is a playable character and a protagonist in Fire Emblem: The Sacred Stones and a DLC character in Fire Emblem Awakening. She is the princess of Renais, only daughter of King Fado of Renais, and the younger twin sister of Prince Ephraim.