If Robert had brought Mya Stone to King’s Landing, what sort of social status/lifestyle could she have had there? Can you give any historical examples of royal illegitimate daughters that were significant figures in their fathers’ court?

I think it would have counted against Mya that her mother was not merel a commoner but a servant to boot, compared to Edric Storm’s mother being a lady of House Florent.

In terms of royal illegitimate daughters – well, depending on whether we count Mary and Elizabeth Tudor, given that their illegitimacy was more a political issue and many people didn’t accept them as such – it’s hard to go wrong with the prolifically promiscuous Charles II’s many, many illegitimate children. With Barbara Villiers (Duchess of Cleveland), Charles had Charlotte Fitzroy, who would become Countess Lichfield, and Anne Fitzroy, who would become Countess of Sussex; with Elizabeth Boyle (Viscountess Shannon), he’d have another Charlotte FitzRoy who became the Countess of Yarmouth; and with Moll Davies (actress), he had Mary Tudor, and married (although later divorced) the Earl of Derwentwater). 

Any other prominent royal illegitimate daughters, @goodqueenaly?