Is there anyway to sort a shared photostream according to the person who posted to it?

The situation is, my family went to disney last month and took lots of pictures and shared them all to the same stream (iPhones and camera). I just want to import all the ones that are not mine (ie, they are not in the imported event or my own personal phootstream) without reimporting (duplicating) all the ones I shared. (on the mac) The stream is about 80% my own pics since I was in charge of the camera. Is there a way to sort them by the person who posted so that I can select theirs only? If not, when I import the photstream, will it recognize duplicates? Thanks in advance!