Jon snows parentage (SPOILER)

A+B=JAshara Dayne of Starfall, the sister of Ser Arthur Dayne, was a famous beauty, beloved by Barristan Selmy and Brandon Stark. Brandon Stark was the older brother of Ned Stark, who was betrothed to Catelyn Tully before being strangled by the Mad King. A notorious womanizer, Brandon was captivated by Ashara during the Tourney of Harrenhal, with Barristan Selmy lamenting the fact that she 'looked to Stark' instead of him. After the events at the Tower of Joy, Ned Stark went to Starfall to return her deceased brother's sword, Dawn. Rumor has it that the beautiful Lady Dayne commited suicide for unknown reasons which Selmy speculates on:"Even after all these years, Ser Barristan could still recall Ashara’s smile, the sound of her laughter. He had only to close his eyes to see her, with her long dark hair tumbling about her shoulders and those haunting purple eyes. Daenerys has the same eyes. Sometimes when the queen looked at him, he felt as if he were looking at Ashara’s daughter ...But Ashara’s daughter had been stillborn, and his fair lady had thrown herself from a tower soon after, mad with grief for the child she had lost, and perhaps for the man who had dishonored her at Harrenhal as well. She died never knowing that Ser Barristan had loved her. How could she? He was a knight of the Kingsguard, sworn to celibacy. No good could have come from telling her his feelings. No good came from silence either. If I had unhorsed Rhaegar and crowned Ashara queen of love and beauty, might she have looked to me instead of Stark?He would never know. But of all his failures, none haunted Barristan Selmy so much as that."From this, we know that Ashara 'looked to Stark', that she had a stillborn child (which Barrisatan believes to have been female), and that she commited suicide for ambiguous reasons.Now, many assume that the 'Stark' referenced here is Ned, but that is unlikely. First of all, the 'loss' of Brandon was much more permanent and shattering than the 'loss' of Ned would have been, one man being dead, the other being married. Second of all, Edric Dayne claimes that he and John shared a Wetnurse, and also seems to hold no animosity towards Ned, even seeming a bit starstruck by him. This is odd, if the widely rumored story is true: That Ned killed Arthur, and drove Ashara to suicide. What could he have done? Well, this exchange offers some pretty telling clues:"They whispered of Ser Arthur Dayne, the Sword of the Morning, deadliest of the seven knights of Aerys’s Kingsguard, and of how their young lord had slain him in single combat. And they told how afterward Ned had carried Ser Arthur’s sword back to the beautiful young sister who awaited him in a castle called Starfall on the shores of the Summer Sea. The Lady Ashara Dayne, tall and fair, with haunting violet eyes. It had taken her a fortnight to marshal her courage, but finally, in bed one night, Catelyn had asked her husband the truth of it, asked him to his face.That was the only time in all their years that Ned had ever frightened her. “Never ask me about Jon,” he said, cold as ice. “He is my blood, and that is all you need to know. And now I will learn where you heard that name, my lady.” She had pledged to obey; she told him; and from that day on, the whispering had stopped, and Ashara Dayne’s name was never heard in Winterfell again."What is important to notice here is that Catelyn never asks Ned about Jon directly; she asks him about Ashara Dayne, and Ned himself, in an icy rage, confirms that Ashara Dayne and Jon Snow are related. And as the earlier presented evidence suggests that it wasn't Ned that 'dishonored' Ashara, it is most likely that his brother did, leading to her eventual suicide. But was the child stillborn? And what did Ned do which made House Dayne forgive whatever problems he had had with it? One compelling possibility which brings all of these threads together: that the child lived, and, having a stronger claim to Winterfell than any of Ned's children, and a strong claim to Starfall, as the female line can inherit in Dorne (especially if the, at the time, unwed Brandon Stark had secretly eloped with Lady Dayne; something which would always be a possibility since they were both dead before being wed), was brought back to Winterfell by Ned and raised in secret as his own, thoroughly illegitimate bastard son. This gets rid of a thorny succession issue in both Starfall and Winterfell, and basically ensures that Edric will inherit without contest. But I think that something more happened. I believe that Jon was swapped with Lyanna and Rhaegar's actual child: Daenerys Targaryen.R+L=DLet's get the biggest stumbling block out of the way. WAIT! Daenerys was born to Queen Rhaella on Dragonstone! Well, how do we know this? Who is the ultimate source of this story? Viserys. And Viserys is an unreliable narrator. We know this by contrasting Danny's early childhood memories with what she has been told. Viserys had told her that they grey up in Braavos. These are things that Danny remembers from her childhood:1. A big house with:a. A red doorb. Carved wooden beamsc. A lemontree outside2. Smells of:a. Hot sicknessb. PerfumeThere are some big problems with this. The most famous one of these is the lemon tree. Recall this exchange between guards in Braavos:“Seven hells, this place is damp,” she heard her guard complain. “I’m chilled to the bones. Where are the bloody orange trees? I always heard there were orange trees in the Free Cities. Lemons and limes. Pomegranates. Hot peppers, warm nights, girls with bare bellies. Where are the bare-bellied girls, I ask you?”“Down in Lys, and Myr, and Old Volantis,” the other guard replied. He was an older man, big-bellied and grizzled. “I went to Lys with Lord Tywin once, when he was Hand to Aerys. Braavos isnorthof King’s Landing, fool. Can’t youread a bloody map?”Lemon trees require a subtropical climate; Braavos is consistently described as cold, damp, and windy with freezing rain being somewhat common. Lemon trees would never be able to survive in this environment.Another is the wooden beams:"There's no more wood." Dareon had paid the innkeep double for a room with a hearth, but none of them had realized that wood would be so costly here. Trees did not grow on Braavos, save in the courts and gardens of the mighty. Nor would the Braavosi cut the pines that covered the outlying islands around their great lagoon and acted as windbreaks to shield them from storms. Instead, firewood was brought in by barge, up the rivers and across the lagoon. Even dung was dear here; the Braavosi used boats in place of horses."Wood is an extremely precious comodity in Braavos; the city is composed almost entirely of stone. A house with intricate wooden beams is highly unlikely.And a third is the smell of Braavos:The city is consitently described as smelling of salt spray, fish and brine, yet Dany remembers none of those smells.All of these facts indicate that Dany has been lied to by Viserys. Couple this with the fact that an oft-repeated mantra from Quaithe to Dany is 'Remember who you are'. Dany does not know something about her past, something which has been hidden from her by Viserys. If this is what Quaithe's command is referencing, then it is something important. If she is Rhaegar's daughter instead of Rhaella's, that would certainly qualify. So let's go over the evidence.What does Viserys have to gain from lying?Everything. If Dany is his younger daughter, he can marry her off for political gain, which he does. She has no claim whatsoever over him. However, if she is the daughter of his older brother, she is much farther outside his power. Just imagine Cersei's Uncle Kevan commanding her to understand the disparity in power between the daughter of the heir and a younger sister. Or imagine Sansa's Uncle Benjen trying to marry her off. If Daenerys is not Rhaella's daughter, it cuts down severely on Viserys's leverage, and he needs all the leverage that he can get.The PromiseNed makes an nondescript promise to his sister before she dies, and is consistently haunted by that promise. Why would he be so thoroughly haunted by thoughts of failure if the promise was about Jon? Jon had joined the Night's Watch, as planned. He was months away from King's Landing. And Ned isn't tormented by thoughts of broken vows when he deals with or thinks about Jon. He is haunted by them while dealing with the attempts to assasinate Daenerys. He reacts EXTREMELY negatively to the prospect in the first place. He goes to huge lengths to protect her. All of this points to the fact that SHE was the one whom he had promised to protect.The House of the UndyingDany has a glimpse into the past, during which she sees Elia, Rhaegar, and a newborn Aegon. At the end of the exchange, the apparition seems to stare straight at her, and declares that 'the dragon has three heads' and that 'there must be one more'. Elia, after giving birth to a daughter and a son, is unable to birth a third child. The prophecy regarding a dragon with three heads seems to be a well-known one amongst Targaryen students of prophecy, becuase Maester Aemon recites it on his deathbead, lamenting his inability to guide Daenerys. Many people hold that, Elia being frail, Rhaegar seduced Lyanna for the purpose of producing this 'third head'. The common assumption is that it is John Snow, but both Aemon and Rhaegar himself, in the apparition, imply that it applies to Daenerys. Dany also more closely follows the historical model: Two women and a man (Aegon, Visenya, and Rhaenys). By that model, the third 'head' would be another female, not a male.All in all, I think that it is more likely that Lyanna and Rhaegar had a daughter, Daenerys, whom Ned spirited away, switched with Jon (his brother's son) at Starfall, and was tormented over having failed to protect her from Robert in his final months.