One legged Robin refers to a regular visitor to our garden over the past few years. He (I am pretty sure it was a he) would sit on your hand and happily feed. He would actually pester us for food when ever we were in the garden or even in the kitchen. He would sit on the window sill or the door handle and peer inside until we opened the door and gave him some food.
He had two legs but one was badly injured, we assume in a fight with another Robin as he was quite aggressive. He would therefore rest his injured leg by tucking it up into his feathers and balance quite happily on the other.
Sadly, we haven't seen him for the past few months and suspect the worst. We think he was about five years old so had a pretty good life, for a Robin. We console ourselves with the fact that he may have gone sooner, given his leg injury, had we not given him so much food. Then again, we did feed him with suet sticks (he was addicted to them) - maybe he had coronary heart disease!