My guess for next year.... Jon Snow is going to be king eventually, and will be fighting along side the dragon queen to defeat the white walkers and then the Lannisters, because he is actually a Targaryen, so he is half brother to the dragon queen. His father is the mad king, not Ned Stark. Ned Stark’s sister gave birth to Jon Snow after she was raped by the mad king.
Nephew, not brother.
His father is the mad king,
Rhaegar is his father, son of the mad king, brother of Daenerys.
His father is the mad king's son - Dany's brother -- so Jon Snow is really her nephew. In their kingdom, that is not a problem so he could end up as her husband after they conquer their enemies. And while the "official" story that Ned told was that his sister was kidnapped and raped, the fact that she made Ned promise to protect her son indicates that the kidnap and rape claim was a ruse.
King Aerys II Targaryen (the Mad King) was the father of:
-Prince Rhaegar (eldest son and heir to the Iron Throne)
-Prince Viserys (got a “gold crown” from Khal Drogo, Dany’s husband)
-Princess Daenerys (Dany on the TV show)
Prince Rhaegar married Princess Elia Martell of Dorne (sister of Prince Doran and Prince Oberyn of Dorne). Rhaegar and Elia had two children. Ser Gregor Clegane (The Mountain, a knight who is sworn to House Lannister) brutally killed Elia and her children during the Sack of King’s Landing. This is the source of the bad blood between Dorne and House Lannister.
Prince Rhaegar is also blamed for starting Robert’s Rebellion when he abducted Lyanna Stark. However, Rhaegar did not kidnap Lyanna. They fell in love, and she got pregnant. The problem was that Lyanna was already betrothed/promised to Robert Baratheon. Lyanna knew that Robert would kill her infant son (due to Robert’s jealousy or because the baby boy was in the direct line of succession to the throne, but probably both).
The only question is whether Rhaegar and Lyanna got married (polygamy was uncommon, but it did happen). If Rhaegar and Lyanna did not marry, then Jon’s claim to the throne could be seen as weaker than his aunt Daenerys’ claim, because she is the legitimate daughter of King Aerys. The claims of trueborn heirs usually take precedence over illegitimate heirs, although Jon would be the only surviving heir of Rhaegar, King Aerys II’s oldest son.
But legitimacy isn’t everything. The Game of Thrones is about who can take the Iron Throne and who can keep it.
My understanding of that rumor is that Raegar Targaryn is Jon's father (Dany's brother). Recently read a speculation that it is Tyrion who is the son of the Mad King, having impregnated Tywin Lanister's wife while they were living at the Red Keep.
That one may explain Tyrion's ability to walk up to a couple of dragons and not be eaten. He has Targaryn blood in him.
Also puts a different spin on Tywin always saying to Tyrion that he was not HIS son. Maybe the problem between Tyrion and his father was not about his being a dwarf at all; but, Tywin was actually speaking the truth --- he is not his son.
No, Jon is Daenarys’ nephew. His father was the Mad King’s son Rhaegar, not the Mad King himself.
My guess is Snow won’t find out about his lineage until he is married to the blonde chick with the dragons. Ewwww, more incest.