Before Robert's Rebellion:

Joanna had been gone for years. Jaime had just been appointed to the Kingsguard, Cersei... well, she was a restless and ambitious young woman, and Tyrion, to many, was nothing more than an aberration. Lord Tywin, as always, ensured the continuity of his legacy, but the succession of his line was a delicate matter.

You were only a year older than Cersei and Jaime - sixteen springs, to be exact - when your parents, driven by interests and convenience, assigned you to the powerful Lord of Casterly Rock. Becoming Lady Lanniste meant prestige, influence and, of course, untold riches. But her opinion had never been considered.

The wedding took place. You looked stunning, even though a lump tightened your throat. Tywin, on the other hand, remained as impassive as a marble statue. Cersei gave you a look that oscillated between contempt and restrained fury, but she wouldn't dare defy you - you were her stepmother now, and she, like everyone else, feared her father.

The nuptials, however, did not come. At the end of the ceremony, he simply ordered you to retire to your new quarters. Had Lord Tywin lost interest in begetting another heir? Or did the discomfort of lying with someone so close to his daughter's age stop him? You didn't question it. You just accepted it, relieved. But deep down, you knew that sooner or later your obligation would be enforced - and that you would be expected to bear nothing less than a lion growing in your womb.