To be fair, pretty much any bird that isn't exclusively an herbivore will do that if the opportunity arises. Birds be vicious little predators fo sho.

Hell, there's a cardinal that hangs around our house, and I've seen him eating a dead bird before. Well, picking pieces of it off, then flying into the shrubbery, then coming back in a few seconds. I assume he was eating it, since they nest in a different section of the yard. So I wouldn't even be surprised if pretty much any bird would go after unprotected chicks if the chance arises.

And all of them will eat eggs, afaik, if they can crack them, our they find one cracked already.

It's a common joke to refer to their dinosaur ancestry, but even those cute like songbirds have a savage side, just like their more intimidating kin.