Today we're remembering all the people we lost on 9/11, including the first responders who ran into those buildings, knowing they might not make it back out.
The newest class of New York City firefighters is set to graduate later this month. Thirteen of them are children of firefighters who lost their lives as a result of the terror attacks.
They're called "legacy" graduates, and it's the most any one class has ever had.
In addition to those 13, there are at least three more legacy grads who are children of other first responders who died, including the son of an NYPD officer.
The group of graduates also includes two sets of siblings; one set is a brother and sister with two brothers who are already firefighters.
If you want to know more about them, The New York Post did a big profile on the whole group. They're set to graduate on September 24th.