Thanks for the help everyone. I can rule out the Flicker ID. I know those birds very well. The juvenile Robin is interesting. I've looked at a bunch of photos and there is a great deal of variation. Some looked fairly similar and I get this is the most likely possibility. Still, none of them looked as close as pictures of the Fieldfare did - even though I know this is an unlikely possibility. Would the Juveniles be at least as big as the adults they were with? The 2 I saw seemed even a bit bigger, but let's say they were close to the same size - does this fit? Also, what about the song they were making? It was nothing like any of the Robin calls I've ever heard. It wasn't a "song" - not melodious or musical in any way - it was chattery, squeaky, kinda high pitched and was repeated a number of times, but to say repeat makes it seem like a song - more repeated pattern-less (I think) squeaky chattering.
Please keep new ideas coming. I see why the Juvenile Robin makes the most sense - when I look at the photos, I can see I would have been baffled ID-ing some of the variations I saw. And yet, I don't feel 100% sure about the Robin call and want to keep considering possibilities.
Thanks again,
Rick