Cooper's Hawk

Agree with the Cooper's hawk IDs - and I learned a quick ID tip off the tail! :)

Here is a handy info page that compares the sharp-shinned and coopers side by side with photos and ID words, including juveniles: http://static.birds.cornell.edu/pfw/AboutBirdsandFeeding/accipiterIDtable.htm

Definitely a Cooper's Hawk, you can clearly see the rounded tail. Nice spotting!

Based upon the shape of the tail and the apparent size of this bird, I believe it is a Coopers Hawk. Nice spotting! It can be very difficult to tell the difference between Coopers Hawks and Sharp-shinned Hawks, but the rounded tail feathers in your second photo suggest that this is a Coopers.

I am in favour of the Sharp-shinned Hawk, because it has the white vent too, something that Cooper's Hawk does not have, I believe.

Not going to us "Suggest an ID" because I am far from certain, but I think you have a cute little Sharp-Shinned Hawk there.