Photo Gallery: Sept. 11 Anniversary 21/33

NewYork Firefighter Zachary Fletcher embraces his mother Monica Fletcher after finding his twin brother Andre G. Fletcher's name engraved at the south pool of the National September 11 Memorial during a ceremony marking the 10th anniversary of the attacks at World Trade Center, Sunday, Sept. 11, 2011 in New York.  (AP Photo/Mary Altaffer)