Now that you mention it, I don't think it was shown in the show, if I recall correctly I saw some reference to this in one of the older GoT threads for last season. I can't vouch for how accurate it is though. So it could be totally wrong, and I guess since they didn't put it in the show, it couldn't really be used as a valid motivation for her character in the show itself.
She wouldn't have to marry and bear a child with Bi-boy. History Cersei is technically her parents' oldest child, although her twin Jaime was born mere moments later, clutching her heel. The twins were nine years old when their brother Tyrion was born, killing their mother and causing their father to become cold and bitter. Cersei has been haunted since childhood by a prophecy made by a wise woman, Maggy the Frog, who was reputed to have magical powers. The woman correctly predicted Cersei's marriage and mutual infidelity with a king. She went on to prophesy that Cersei would outlive all her children, who would die as kings and queens, and that after everything she had was taken away by a younger and more beautiful queen http://awoiaf.westeros.org/index.php/Cersei_Lannister
Yes, this does give it away, so don't click if you don't want to know whodunit. It is legit in the sense that it is only using evidence from the first two episodes of the season, so the evidence is there for people at large to know definitively who the poisoner is. But frankly, if I hadn't read the books I never would have noticed this stuff in a million years. Even though the evidence is there, it's so subtle that I think it's clear they mean it to remain a mystery, at least for a while.
If you want to know who/how it was done based purely on what we see on screen (i.e. no book spoilers), click below. Spoiler <iframe class="imgur-album" width="100%" height="550" frameborder="0" src="http://imgur.com/a/2DtPH/embed"></iframe>
Regarding Joffrey's murder: Spoiler Correct me if I'm wrong, but I thought it was Lord Varys... Or am I thinking something else?? It's been a while since I read the books.
I've read the books. Spoiler You're wrong. Don't want to say more than that in this thread, but feel free to ask and refresh your memory in the book readers thread.
Spoiler Sansa is actually taken away by Littlefinger, who hired Ser Dontos, I think. Ser Dontos is the one who gave Sansa the jewels (for more on that, look at Commodore's spoiler). So most likely, Littlefinger and the Queen of Thorns are working together.
I laughed when Oberyn said "hello" to the gymnast and Tyrion responded with a greeting. Then got the "not you" back. Hilarious. He's had a rough day.
i watched it again and it really was grannie tyrell who poisoned the king. the question now is why???
She was concerned with her granddaughter's life when she interrogated Sansa. She wants the Tyrell's to have power, which is why they pursued a marriage to the king. However, learning of Joffrey's ways (which she suspected anyway) makes her plan a have your cake and eat it too type of deal maybe?
