Daenerys Targaryen is the exiled female heir of the Targaryen house and has dragon blood. She joins the Dothrakis when she is married off to Khal Drogo by her brother Viserys.
Daenerys: Get him out of my sight.
Jorah: Khaleesi please, I just need a moment of your time. I brought you a gift.
Tyrion: It's true, he has.
Daenerys: Who are you?
Tyrion: I am the gift. It's a pleasure to meet you, your grace. My name is Tyrion Lannister.
Handmaiden: A trader from Quarth told me that Dragons come from the moon.
Daenerys Targaryen: The moon?
Handmaiden: He told me the moon was an egg, khaleesi. That once there were two moons in the sky, but one wandered too close to the sun and it cracked from the heat. Out of it poured a thousand thousand dragons and they drank the sunâ€™s fire.