You can read all about the sad tale here.
Their eyes were not open when they were found, which makes it more amazing that they survived (although there were 3 and one did not make it). ACC received the two remaining sisters, now named Yonah and Athena. Athena is larger with a white spot on her chest (hope I didn't get that backwards, but some of you zoo folks will correct me, I'm sure).
but aren't they just cute?