FRANK SILLER: 'I love you, brother' -- the 9/11 loss that inspired a mission of service

PROGRAMMING ALERT: Watch Tunnel to Towers Chairman and CEO Frank Siller discuss his new book " Let Us Do Good ," on "The Five" on Sept.

1 on Fox News Channel at 5 p.m.

ET.

There are moments in life that divide everything into before and after.

For me, one of those moments came on September 11, 2001 , when a firefighter calling from Ground Zero told me what I already feared but was not ready to hear: my younger brother Stephen was not coming home.

In that instant, my family’s life changed forever, and so did the course of mine.

Even though I knew that it was probably an exercise in futility, I also kept trying to call Stephen from my Nextel phone, on September 11, hoping that perhaps he had somehow already made it over the Verrazzano Bridge and back to Staten Island.

We had the same phone; it was both a cellular phone and a walkie-talkie, which was popular in the early 2000s.

I kept pressing the button on the walkie-talkie part while I called out for Stephen.

He did not pick up.

I called again, and again, and again.

There was no answer—only an eerie silence.

I wound up doing that all night and well into the next few days.

I LOST MY WIFE ON 9/11.