It was essential for both of the Singh children to leave very early on the day of the attack -- by 6:20 a.m. -- because their roles were so crucial at the conference breakfast at Windows on the World.

Khamladai, 25, as an assistant banquet manager, would be greeting the participants at 8 a.m.; her little brother, Roshan, 21, was arranging the audio-visual presentation. There were 600 guests, after all, and preparations had to be flawless. So they left the family home in Woodhaven, Queens, together as they always did, caught the A train and arrived by 7 a.m.

If brother and sister were extremely close, doing just about everything together, it is true that Khamladai often had the tighter schedule: after her day at Windows, she studied computer programming full time at Borough of Manhattan Community College. There were times, though, when Roshan was equally pressed, thanks to his duties in the Army National Guard.

Now their mother, Toolsiedai Seepersaud, waits in a quiet house for her only children with their stepfather, Jamil Awan. "I am just hoping they are together," she said.

   9/11: The Reckoning