Answer:
What two things can always see what the other sees, but can never see each other?
You must keep this thing. Its loss will affect your brothers. For once yours is lost, it will soon be lost by others.
Different lights do make me strange, thus into different sizes I will change.
What do you throw out when you need it but put away when you don’t?
Always wax, yet always wane: I melt, succumbed to the flame. Lighting darkness, with fate unblest, I soon devolve to shapeless mess.
I have two eyes in the front and a lot of eyes on my tail