Updated

The thief who stole an American flag stolen from the Long Island family of a firefighter killed on 9/11 apparently thought better of keeping it after hearing of its significance. The guilt-stricken thief reportedly put it back properly folded in a triangle on the Fourth of July with a note that said, “I am so sorry. I had no idea.”

The flag flew over the World Trade Center during recovery efforts. The September 11th Families Association gave it to Melissa Brengel in honor of her 29-year-old brother, Jonathan Ielpi, an FDNY member who died when terrorists destroyed the World Trade Center.

Brengel reported the flag missing from her home in Huntington Station, L.I., on Tuesday.

“Good news,” she said on Facebook, according to the New York Post. “It was outside the house when we woke up."

The thief made his apology in a handwritten note.

"The flag means so much to me and my family and we are so happy and grateful that it was returned and we are able to display it again, although this time it will be put in a proper case and displayed in the house," Brengel said.

Click for more from The New York Post.