Bharbo

Bharbo was a Dothraki khal and the father of Khal Drogo.

Lord Snow
Rakharo mentions to Ser Jorah Mormont that his father was a bloodrider to Khal Bharbo and was a great warrior.

You Win or You Die
Drogo mentions his father's name when he vows to cross the Narrow Sea and conquer the Seven Kingdoms in response to the attempted assassination of his pregnant wife, Daenerys Targaryen.

In the books
In the Song of Ice and Fire novels, Bharbo is mentioned in the same way as in the TV series; Drogo refers to him when swearing to retake his wife's father's throne.