Twenty-one years after the Sept. 11 terrorist attacks, the families who lost loved ones at the World Trade Center and are still seeking to hold on to them one last time.

For these families, who have yet to receive any remains of their loved ones, the closest they can get is a special section of the National September 11 Memorial & Museum located at what was once the foundation of the north tower of the World Trade Center.

While the museum’s repository serves as a somber memorial ground for those families that have no physical proof that their loved ones perished on 9/11, the forensic team at OCME has been testing samples of those remains to try to make positive identifications in their own lab in Manhattan. And even though the team said the task has been daunting for 21 years and counting due to the sheer scope of work, they are still determined to give these families closure.