Kira Sinn
However, I suspect you might be thinking of a different "Kira" - perhaps Kira, a character from the manga and anime series "Naruto", or another fictional character.
The Anglo-Irish Treaty of 1921, which established the Irish Free State, led to a division within Sinn Féin. Éamon de Valera opposed the treaty, while Michael Collins and others supported it. This split led to the formation of two separate parties: Cumann na nGaedheal (later Fine Gael) and Fianna Fáil. kira sinn
That being said, here's a post on Sinn Féin, the Irish political party: However, I suspect you might be thinking of