BUFFALO, NY-- A 12-year-old girl was hurt after she fell down a sewer hole in South Buffalo.

The incident happened on S. Legion Drive and Rutland Street around 8am.

Fire officials say Grace Knox fell about 12 feet and was down there about an hour before she was found. A passer-by heard her screaming for help and called first responders. Firefighters say it took about two minutes to rescue her. She suffered a lower leg injury in the incident.

The city claims they checked with the sewer authority and confirmed no work was being done in the area around the time of the incident.

South Buffalo District Police are now trying to find out why it was removed and how. The city says man-hole covers weigh about 150 pounds, and workers use a special tool to lift the cover out of the ground.

The way her doctors, city officials and her family explain it Grace Knox is a very lucky little girl. "I believe an angel grabbed her and helped her down," Grace's grandfather, William Miles, tells 2 On Your Side's Emily Lampa. "And an angel was there to pick her back up again."

Around noon on Tuesday, Grace posed for a picture in her hospital bed. Her grandfather sent it to WGRZ. Despite recovering from hypothermia and preparing to go into surgery to fix a broken ankle, she was all smiles.

This seems understandable considering just about four hours earlier she was 12 feet below ground in the sewer hole. She was trapped, unable to climb out on her own.

William tells us how Grace described the experience, "Very dark, very cold, And very lonely. She was screaming for an hour and a half. Finally a good samaritan who was out for his daily walk heard her screams and came to her rescue. I thank him so much."

"When the crews arrived, the girl was down in the hole," explains Assistant Fire Commissioner, Johnathan Eaton. "We used the assistance of a ladder and a rope, and she actually helped herself for the rescue."

Her family met her at the hospital and were relieved that her injuries were not more serious.

But they are considering a lawsuit for the pain and trauma Grace suffered. "It shouldn't have been open," Miles tells Channel 2 matter of fact. "And if it was open, it shouldn't have been left open"

Grace will be observed overnight at the hospital and Wednesday she'll go into surgery for her ankle.

In terms of the investigation, if police find the person responsible for removing this man-hole cover they could be facing charges of attempted larceny, criminal mischief, even vandalism.