Bullsh!t
We had this happen to us a couple of years ago. My daughter (now 11) took charge. We placed the sparrow is a small box. My wife picked up baby bird food at a pet store and fed the bird. It grew and grew. The bird was tame and we eventually released it.
My daughter still looks to the sky and speaks of Feathers.
We did the same thing. The pet store had a mix with water stuff and a plunger to suck it up and feed him with. He would come running when he saw me with it. Lol
The myth about birds rejecting their young after they are touched by humans is also untrue.