I need some help here with iPhoto. I want to know how to add a picture to a roll after that roll has been created. For example, I went to Greece and added all my pictures from Greece into iPhoto as a roll. Now a friend has sent me some pics that he took on the trip also and I would like to add those pics to the roll I had previosly imported. How can I do this? Everytime I drag in the pic that my friend sent me it puts it in a new roll. I want it to be a part of a previous roll. How? Thanks.