Combie the sweet rooster boy suddenly loss control of his legs and could no longer walk. Since this video I have discovered that too many treats for chickens can actually cause vitamin deficiencies that can cause them to lose the ability to walk and other illnesses too. Chickens need a complete balanced feed as their primary diet and only occasional treats. If only we had known.
Update on Combie (2014-07-26)  ​​"Been spending a lot of time with him.  He's determined and full of chattiness but I'm not sure he'll make it through.  He can no longer stand for more than 15 seconds without stumbling backward and sitting on his bum.  This frustrates him.  He did spend a good hour out in they sun laying down, managed to preen his wing feathers and squeal at some crows flying overhead.  He does not seem to be in any pain, more frustrated than anything else.  He's eaten wild strawberries, watermelon, soft boiled eggs, a variety of seeds and blueberries today.  I'm not sure where it's going, but at his age, I have my doubts if he'll recover :(​".--Colorful Canary
References: Video: Combie needs your help. (July 23, 3014).  ​https://www.youtube.com/watch?v=ocMGrJKyTYo