The bill is wrong for Robin and they have a lot more streaks on their breast. My guess would be an Eastern Towhee, male, but this is looking at pictures I found in a search. I cannot see enough of the breast on your pictures to be sure. Was there white going down the center?
Ah, I didn't mention that it looks like a juvenile. You mentioned fledgling in your original post and I had that in my head, but didn't type it. If you scroll down a little on the link I gave you, there is a picture of a immature, male Eastern Towhee. Yours looks older than a fledgling, but it is still young. Sorry about that.
I hope someone confirms this because I feel so uncertain with my ID skills, especially if they are not those who frequent our yard very often. Most often I can tell the Meadowlarks apart by song and if I can get a good look at certain field markings, but get me out of my "comfort zone" and I just fall to pieces.