What's the age difference between Rhaegar and Daenerys?

What's the age difference between Rhaegar and Daenerys?
Viserys was born 17 years after Rhaegar, and Dany followed another eight years later. So Rhaegar would have been 25 years old when Dany was born, if Robert hadn't killed him.
Is it likely that Daenerys is Jon Snow's aunt?
- Short answer… 100% likely. As Rhaegar is Danaerys’s sibling, and Jon’s father as shown by the above diagram, then Dani is indeed Jon’s aunt. Being as they are Targaryen, and that family is known for “keeping the bloodlines pure” as Cersei puts it, it wouldn’t necessarily preclude them from marriage. Hmmm…. Daenerys is Rhaegar’s sister.
Who is the mother of Jon and Daenerys Targaryen?
- The pair’s mother is the late Rhaella Targaryen, sister and wife to Aerys, who died giving birth to Daenerys. This means Dany is Jon’s aunt, and Viserys is his uncle.
Why did Daenerys and Jon fight on Game of Thrones?
- What might cause more of an issue for Dany is Jon's place in line for the Throne. Daenerys' claim to the Iron Throne has always been that her family was unjustly removed from power and that she, as the only living Targaryen heir, is the rightful ruler of Westeros.
How is Jon Snow related to the Targaryens?
- The History of Aegon Targaryen & Jon Snow’s Family. Jon Snow’s real name is Aegon Targaryen. Here’s a history of other Aegon Targaryens. You can learn even more about them in the Game of Thrones Wikia.