Did Tywin Lannister know about Jaime and Cersei?

Tywin Lannister, Cersei and Jaime’s father and their only parent that survived long enough to watch them grow into adulthood; he was not aware of their relationship until Cersei and Jaime were grown and he was nearing his deathbed.

Did Tywin know about Arya?

Some fans have wondered if Tywin was ever suspicious of her true identity and realized she was a Stark, but this is unlikely. He never would have passed up the chance to use her as a hostage or bargaining chip against Robb had he realized who she really was.

What if Tywin Lannister had lived?

If Tywin had lived then the suicide mission to retrieve a wight from beyond the Wall probably would not have happened. However, if for some reason it still did and Jon and Daenerys travel to the Dragonpit to seek a truce, then there is no way Tywin would have allowed his enemies to leave King’s Landing alive.

What if Tyrion was the hand of Daenerys Targaryen instead of Cersei?

Instead of waging war against Cersei as Daenerys’ Hand, Tyrion would be in open conflict with the father who despises him. Tywin always scorned his son due to his disability and seeing Tyrion at the head of the Targaryen army would have confirmed his bias opinions.

What would have happened if Cersei didn’t destroy the sept of Baelor?

Without the Faith Militant provoking her wrath, Cersei would have no reason to destroy the Sept of Baelor. This means that Margaery and Loras would never have perished and there would be additional players in the game of thrones. With Margaery alive, Cersei is further ousted from power as opposed to seizing the Iron Throne.

What would have happened to Cersei if Tywin was alive?

Tywin had commanded Cersei to marry Loras Tyrell before his death, though the Lannister queen refused. Had he survived then there is no doubt that Tywin would have forced her to remarry as well as finding a suitable bride for Jaime, who with Tyrion in exile would be the sole heir to Casterly Rock.