The Obama Administtation carefully selected 50 9-11 families to join them at the White House this week. At least one declined.
The Sun-Sentinel reported:

As 50 carefully selected families prepare to join President Barack Obama for a ceremony at the World Trade Center site Thursday, one of the invited 9/11 families have decided to pass on the Commander-in-chief’s visit.

Although many consider it to be a once in a lifetime invitation, the Vigiano family of Deer Park, Long Island have respectfully declined.