[@Gowi]

You'd have to go back quite far into the Tyrell household. I would imagine someone like Lord Merlin Tyrell, or Garland's great grandad (dad of Jaime "The Green" Tyrell, who was dad to Gregor, Moryn (Garland's father) and Willas Tyrell- so not a current one, but a Rose that joined the Fish long, long ago.