They were promised a place to mourn their loved ones, display their photographs and educate their children and the children of strangers about exactly what was lost on 9/11. But today, family members of those killed have no completion date for the museum that is to be built alongside the Sept. 11 memorial at ground zero — and many are upset.

"The memorial is open, but that's only half the tribute to those who were killed," said Patricia Reilly, who lost her sister in the attacks. "The museum is the place where they're going to tell the story about the people — who they were, where they were, what they were doing and what happened to them that day."

Construction of the museum — originally scheduled to open on the 11th anniversary of the attacks — has largely ground to a halt amid a financial dispute between the Port Authority of New York and New Jersey, which owns the site, and the foundation that controls the memorial and museum.