Easy question???

Let's see...
- Edward/Gilbert (prince of Damcyan)

Hemmmm... well....
- Is Luca the daughter of King Giott?? (If so, she's a princess)

Baron, no... Fabul, no...

Oh wait! Edge! He's the rightful heir of Eblana!... That makes three...

Mysidia, no... Sylph cave, ... duh? Cecil and Yang have no royal blood and ascend to the throne directly... I don't think FuSoYa really exists.

Golbez is the prince of darkness? nah... won't work...



I only think of three (Gilbert, Edge and Luca), but since I must miss two dozen princes/princesses, I'll wait...