Allegedly Lyanna was at a Tournament with her brothers and Rhaegar won it and gave her some flowers or something. Lyanna disappears from Winterfell, is said to be with or captured by Rhaegar. Lord Rickkard Stark of Winterfell goes to KL to demand the Mad King make Rhaegar return Lyanna Mad King says fuck you arrests Lord Stark and Brandon Stark heads to KL ready for a fight. Lyanna and Rhaegar are not seen, Robert was engaged to Lyanna but never knew her as Ned often thought to himself. Mad King puts Lord Stark on trial by combat when Brandon arrives...his champion is wildfire. Rickkard Stark burns alive while Brandon is choked to death trying to save him. Robert Jon Arryn and Ned call banners and rebel. Robert kills Rhaegar is battle of trident with a hammer...Lyanna still hasn't been seen. Ned goes to sack KL, Jamie kills Mad King while Tywin's forces betray Targaryen trust and sack KL for Robert. Lyanna is not in KL so Ned goes to the Tower of the Joy in Dorne to rescue his sister. She is there yelling for Ned while being guarded by Rhaegar's top Knights. Ned and Howland Reed survive a battle with the Knights. Lyanna is alive surrounded by blood and makes Ned promise her something which he does, Lyanna dies and Robert vows to kill the whole Targaryen line while Ned returns to Winterfell with his bastard and Howland Reed returns to the swap for some frog gumbo