The Construct Theory

(Going off the same basis as the Phoenix theory http://pastebin.com/9Bf6shQK)

Some theorists believe that the wish fulfilment was a mirror of the story of Pygmalion, where the king Pygmalion is made into a sculptor who fell in love with an ivory statue he had crafted with his own hands. In answer to his prayers, the goddess Aphrodite brought it to life and united the couple in marriage.

Desna created a construct or new person in the form of Onas's Sister. This would explain why Felicia would know so much of bardic music, knowledge of the land and lore even though she is an amnesiac because the God of Travellers filled her with the knowledge. Desna has also been know to work with Shelyn the God of Arts which means that creating this kind of person would be an easy task.