A Robin? That was an owl, hawk, or eagle. Look at the gold eyes. Robins have narrow black slits for eyes. Hawks and other birds of prey have a line of bone above their eye for eye protection during sustained high pressure flight.
Also, look at the feather coloring. It is a distinct hawk, eagle, or owl coloring. Nothing even resembling a Robin.
The size of this baby bird is also characterization of a young bird of prey. This bird is just a tiny bit smaller than a full grown Robin.
This is definitely a bird of prey and should still be turned over to the proper animal identification specialists should you have the bird still.
I am sorry to hear about this bird though. Makes me sad.