"He was always running late, but I do remember it was a beautiful morning," Faughnan said. "I was getting bagels at this bagel shop and I looked up and there was a TV, and I saw the first plane hit the building. I was like, 'Oh my God; that's where Chris works.'"

He worked on the 105th floor of the north tower, above the plane's impact. More than 650 employees of his firm, Cantor Fitzgerald, were killed in the attack.

"As both towers came down, I don't think I completely believed that he was gone," Faughnan said. "But it was pretty quickly that I realized that he wasn't coming back."

At just 37 years old, Chris left behind his wife and three children, ages 2, 4 and 7.

"Liam just kept saying, 'When is Daddy coming home?' Juliet was like, 'I knew something was wrong when you sat us in front of the TV, put some cartoons on and gave us a bucket of candy,'" Faughnan said.

Ten years later the family cherishes photographs and keepsakes, such as Chris' baseball glove and notes written to the children. A letter written to his daughter Siena states: "Whatever happens there is one thing of which I am certain, that I will love you more than anything else in the world, more than life itself."

In 2003, Faughnan and her children moved back to Colorado away from the physical reminders of the attack, but the memories have yet to diminish.

"I'd say I pretty much think about it every day, not in detail, but in some small way I think about it," Faughnan said.

She believes the loss of her husband was so sudden and devastating that even 10 years later, there's no such thing as closure.

"I think the key is how you live with it, because you can't not live with it," Faughnan said. "So you learn to just keep it in your heart and do the best you can."

On Sunday, the 10-year anniversary of the terrorist attacks, the Faughnans will attend a ceremony at the Broomfield 9/11 Memorial. Chris' brother, Mike Faughnan, is scheduled to speak at the event, which begins at 11 a.m.