ShadowTheKitten got it correct! She/he guessed something... I'm too lazy to check. I'm pretty sure it was Micah, anyway, here's the next riddle:

I was born to white,
My father kind, but dark.
When I was an apprentice I found out some,
I was... Part of this thing.

My sister was sent as a spy,
To the hawks of the dark.
The great battle happened before my eyes,
Fire will save the Clans.

Good luck!
~Night