When Gemcutter Buccaneer enters the battlefield, it triggers, creating a tapped 2/2 Cat or 3/1 Dog creature token due to Jinnie Fay.
When the Cat or Dog enters the battlefield as a Pirate due to Leyline of Transformation, Gemcutter Buccaneer triggers, creating a tapped 2/2 Cat or 3/1 Dog creature token due to Jinnie Fay.