In A Feast for Crows, Jaime recalls a certain Targaryen King Aenys, second of his name:
Piety and devotion. It was all he could do not to laugh. The walls had been bare on his first visit too. Tyrion had pointed out the squares of darker stone where tapestries had once hung. Ser Raymun could remove the hangings, but not the marks they'd left. Later, the Imp had slipped a handful of stags to one of Darry's serving men for the key to the cellar where the missing tapestries were hidden. He showed them to Jaime by the light of a candle, grinning; woven portraits of all the Targaryen kings, from the first Aegon to the second Aenys. "If I tell Robert, mayhaps he'll make me Lord of Darry," the dwarf said, chortling.
AFFC - Jaime IV
From what I recall, there has never been a second Aenys. Targaryen Kings are:
- Aegon I
- Aenys I
- Maegor
- Jaehaerys I
- Viserys I
- Aegon II
- Aegon III
- Daeron I
- Baelor
- Viserys II
- Aegon IV
- Daeron II
- Aerys I
- Maekar
- Aegon V
- Jaehaerys II
- Aerys II
So where is the second Aenys? I first thought that it may have been a printing mistake in my edition, making second Aerys into second Aenys. But the quote is available in other editions as well so it may be intentional.
Only explanation I can come up with is that the chapter is in Jaime's POV who is not the most well-versed person in history. So it's Jaime's mistake. But is it?
There was also Aenys Blackfyre who claimed to be King, but it is unlikely that noted Targaryen loyalists such as Darrys would have portrait of a pretender in their castle. That's the only way however there could be portraits of two Kings named Aenys.