On 11 September 2001, more than 3000 children under the age of 18 lost a parent: some were still in the womb when the towers collapsed.

Ten years on, as the world marks the anniversary, this new feature-length documentary gives a voice to some of the young people who lost parents on that fateful day, many of whom are speaking out for the first time.

Over the course of a year cameras have followed 11 children from six families across America, charting how one day's events touched children of all ages, religions and backgrounds. Some are only just beginning to comprehend what they lost on that day, while others are entering adulthood and forging their own lives.