“When the sun rises in the west and sets in the east,” said Mirri Maz Duur. “When the seas go dry and mountains blow in the wind like leaves. When your womb quickens again, and you bear a living child. Then he will return, and not before.”
For some reason, every one takes this poetic “fuck you” from Mirri Maz Duur to be accurate. Daenerys Targaryen is infertile.
Certainly, Dany thinks so. She frequently reflects upon how her dragons will be her only children after this moment. She believes that Mirri cursed her to be infertile and to never again bear a living child.
But… Dany is young, impressionable, not great at critical thinking, and prone to putting stock in mystical pronouncements as though they were proven fact. In other words, she’s a Targaryen. This is kind of what they do.
Why do readers also lack critical thinking when it comes to the matter of Dany’s fertility?
House words in Westeros aren’t just a catchy buzzword. They’re a mantra, an ethos to the way that this family works. Even after she’s Lady Stark, Catelyn Tully Stark makes decisions based on the Tully creed family, duty, honour. Daenerys spends her arc from Pentos to Meereen to the Dothraki Sea again figuring out what it means to bring fire and blood.
So if the Tyrells want to grow strong, work their way up the social chain, into positions of power, and have a Tyrell child one day be King on the Iron Throne… why marry the gay Baratheon brother?
This post could also be titled: the Tyrells knew all about the Lannister twins incest, because Mace’s enthusiasm for a Tyrell King only makes sense if he knew that a child born to Renly Baratheon had the best chance of ending up on the Iron Throne.