Btw, if we go by Hagoromo's words, he said something like his mother came from far away land to eat the fruit of that tree and when she ate that fruit she got what we come to know as 'chakra'. 'CHAKRA' specifically, it was never implied that she was granted some dojutsu or something, its just 'plain chakra'. And she passed on that chakra to her two sons, out of which one(Hagoromo) is stated to have dojutsu-Rinnegan and the second, well, not declared yet. It might be possible for his brother to either have a dojutsu different than a Rinnegan or Rinnegan itself(Since they are twins), or no dojutsu at all! To sum it up, I still don't know how could Kaguya have Byakugan, a dojutsu which is definitely weaker than Rinnegan(which is possessed by one/both of her sons)!
Edited by narusaku256, 01 April 2014 - 03:13 PM.