The Queen Regent you mean.
Once I marry Joffrey. I'll be queen.
Game of Thrones Season 3, Episode 4
"to serve as Lord Regent
and Protector of the Realm
Game of Thrones Season 1, Episode 7
I suppose it is former Queen Regent now.
Game of Thrones Season 4, Episode 2
"to rule as REGENT...
Game of Thrones Season 1, Episode 7
Lord Stark, King Joffrey and the Queen Regent
request your presence in the Throne Room.
Game of Thrones Season 1, Episode 7