Hawk Controversy in the Burbs

A friend recently wrote saying he'd been hearing an unfamiliar bird call in his suburban neighborhood.  He decided he had a Harris Hawk, possibly lost by a falconer(!)  I suspected an immature...something.  To my astonishment, I heard the same "Harris Hawk" myself, in my own neighborhood, tonight.  And I am certain we have a raptor, perhaps a Sharp Shinned (pictured) or Red Tail, and certainly a youngster.  But I can see my friend's confusion.  We get connected to the adult calls and songs, lifted from many a recording.  Young birds are still developing, and make the darndest sounds.  I hope we can agree and move on to a new controversy!