About five or six years ago, we found this baby robin outside near our house. It was on the ground. Someone said it was probably a runt and actually pushed or thrown out of the nest by the mother robin because she knew he wouldn't live anyway.
He didn't look hurt when we found him, he wasn't limping or bleeding or doing anything strange. We took him in as a pet, kept him in an open cardboard box, fed him and played with him. Mother-in-Law dug up earthworms from the back yard. We cut them up into little pieces and gave them to him. He ate them all, no complaints. No one said anything about a vet and it didn't occur to me at the time.
No, I didn't demonstrate XD I'd have him standing on one finger and I'd reach up as high as I could, then bring my hand down slowly. He'd flap both wings on the way down. I'd bring my hand down faster and faster, he'd flap faster and faster.
After a few weeks, I'd snap my hand away and I had him doing soft landings a few feet from where I was standing. I took him outside on sunny days and did that on the grass. Mother-in-Law loved to laugh that I was his Flight Coach. =D
He didn't last too long, he died after a few months. But he was a cutie while we had him. =)