Among those is 8-year-old Danielle Spinelli. "I think, well, on Sept. 11, I would tell him not to go to work. I just wish I'd take a time-travel and go back in time and I would also tell him I loved him," she says. Her father, Frank Spinelli, is among those who died.
On Sept. 11, he kissed his daughter goodbye, as he usually did. "He would kiss us goodbye in the morning and it was just one of those things that youd just roll over and just be like 'Dad, its too early,'" says his daughter Nicole, 18. He told me one time, 'Nikki I kiss you and your brother and sister goodbye in the morning to let you know that if anything ever happens to me at work that you would always know that I loved you.'"
Frank Spinelli spent weekends shuttling the kids to soccer, lacrosse and football. By day he was a bond trader, but he hurried home from his new job at the World Trade Center. On Sept. 11, he called his wife so she wouldnt worry.
"Hi honey it's me, plane hit the building. Um. I'm OK. The building's on fire. We're trying to get out. I love you. I'll see you later," he said in the message.
Spinelli was found in the wreckage two weeks before his 45th birthday.
"Every birthday we'd always bake him a cake and we'd always have presents in the dining room," Nicole says. This year, his wife and Danielle baked a cake anyway.
"I just knew that if he was here that he's want a cake so I just decided to bake it with my mom," says Danielle.
How is Michelle Spinelli, his wife, doing? "I guess she's all right, I mean, it's hard for her, says her son Chris, 14. I feel really bad for her. I mean, she, she gets up at one oclock in the morning, just cant go back to sleep.
Danielle tries to understand what happened. I think that these people just took my dad away from us for like no good reason. I don't know why, like if they met him, I know that they'd change their mind. They just went and they were these loving people and they just had to take them away."
This weekend, at Arlington National Cemetery, Tyler and Kelsie Williams said goodbye to their dad, U.S. Army Major Dwayne Williams.
"I was proud of what he did. It was just like I wanted to see his face one last time," says Kelsie.
The Williams' moved to the Washington area with their father and mother, Tammy, three months ago. Dwayne had a new job at the Pentagon. When their father didnt come home that evening, Kelsie, 13, and Tyler, 17, began to write about their dad.
Kelie wrote: "I feel the pain of my father on my heart. I touch my father's face as if he is beside me... I say to myself that he is alive. I dream that he is walking through the door of my house and saying that he is OK."
Tyler wrote: "I couldn't picture life without you and now it's here. It's like the devil looked into my mind and picked my worst fear... I let mom lean on me because now I stand in your shoes. I don't know how you did but you got us through. Now when you look down on me, there is an image of you."
A lot of boys, suddenly young men, see the image of their father in themselves. Mike Shaw is 16, now helping to take care of his sister, Nicole, and his mother, Debbie.
"I now come home every day after school to make sure my moms OK here before I go to bed," he says. "I go in and check on my sister and make sure shes OK, things my dad would have done."
His dad, Jeff, was an electrician in the World Trade Center. He knew every inch of the towers and loved them. When the first plane hit, Debbie called his cell phone.
His son remembers what he told her: "He told her that it was really dark. He couldn't see in front of him; it was just a lot of smoke, and just didnt look good. A couple of minutes later she called him back and at that point he couldnt really hear. He was out of breath and he was saying 'bye, bye I love you, goodbye.'"
More than a month later, Mike still calls his cell phone. "We have his cell phone still connected so when we call we can just hear his voice and then leave a message at the end of the night. I like to call him before I go to bed. It's my way of kind of having a conversation with him for that day." His sister calls, too.
On the Saturday before Sept. 11, Brendan Regan's Little League team got the award for winning the district championship. His dad, New York firefighter Bobby Regan, was coaching that day and Brendan got the hit that won the game.
Lt. Bobby Regan left behind his wife of 21 years, Donna, 12-year-old Brendan, and his 16-year-old daughter Caitlin.
Says Caitlin: "I'm just really happy he was around because I notice that like a lot of my friends' dads, like, they work into the night and I was always really thankful that my dad was around a lot and he spent a lot of time with us."
Regan was going into the World Trade Center about the time Chuck Zion was likely helping colleagues get out. Zachary is Zion's 18-year-old son.
"He had been there in '93 when the building had been attacked the last time," says Zachary. "And it took almost three hours for them to get down from up at the 104th. When I saw the building actually collapse I knew that it was really unlikely that any of them made it out, because 90 minutes to get there, and 104 floors is just not enough."
Chuck loved cooking, football and golf. He was a senior vice president at the financial firm Cantor Fitzgerald Zack intends to follow him there.
Zack says that his America wll be different from his fathers America. "I think people have realized what a special place this is, and what special values that America represents. That it's not something that you just get for free. It's something that you know, you have to fight for really," says Zack.
Chuck Zion leaves behind his wife of 20 years, Carol, as well as Zack, their only child.
"I'm just grateful that I got as much time as I did. There were a lot of kids that were left behind, that won't have known their parents the way I got to know mine. I was at least lucky enough to realize what a wonderful man my dad was before he left," says Zackary.
But Frank Spinelli's children did not know their father as long.
Says Chris: "I always thought that he was gonna be there, and of course there were tons of things that I hadnt learned from him, and hadnt been with him long enough and I really lost a lot of key years in my life with him."
What would Nicole say to her father if she could say something now? "That's really hard," says Nicole. "I would just, after this you look back and you realize that you never again are going to be able to call someone 'Dad' again and just to call someone by the name 'Dad' would just be the one thing that I would want. I would just like to say 'Dad, I love you.'"
"I would play soccer with him," says Danielle. "He would kind of teach me a few pointers. I would, I just want him here. I just want to see his face one more time. And I just miss him very much."
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