The daughter of firefighter Stephen Siller, who died responding to the Sept. 11 terror attacks, continues to honor him by volunteering with a charity created in his name.

The Stephen Siller Tunnel to Towers Foundation raises money for first responders and veterans injured or killed in the line of duty.

Stephen Siller was among many of New York's first responders who rushed into the Brooklyn-Battery Tunnel toward the Twin Towers in Manhattan on Sept. 11, 2001 after hijacked airplanes were deliberately crashed against the iconic skyline.

Olivia Siller, one of Siller's four children, was only 5 years old at the time.

"You get through it," she says of mourning her father. "It was a time of sadness, but also a lot of love."

Now a 19-year-old sophomore at Manhattan College in the Bronx, she is very involved with the foundation.

She says that as the 14th anniversary of Sept. 11 approaches, she wants everyone to remember they're not alone. New York grieves as a city, she says.