Some Are Born Opposites, Some just Turn Opposites

Jackdaw's Cry and Falling Feather from Dawn of the Clans are probably my favORITE SIBLINGS IN THE ENTIRE WORLD OF WARRIORS
They are just... MMMM. I love them. 

(Spoilers for Dawn of the Clans)

Jackdaw's Cry is just one of my favorite characters OF ALL TIME. His relationship with Hawk Swoop, his kits, his friendship with Shattered Ice. They're all good.
His sister, Falling Feather, didn't have as good as a life. She was looked upon as a traitor at Clear Sky's camp! She didn't have a family, only had a couple friends, and was forced to live with rogues that didn't care for her. 
They're lives were quite different, but they loved each other before, and in the end, took each other out of the world as well. That was the saddest death in the entire warrior series. I actually cried (I never cry).