"The floor was still giving in and the dirt was still going down, but I didn't care. I wanted to save my brother," a distraught Mr Bush. "But I just couldn't do nothing."
He added: "I could swear I heard him hollering my name to help him."
Officials lowered equipment into the sinkhole and saw no sign of life, said Hillsborough County Fire Rescue spokeswoman Jessica Damico. A dresser and the TV set had vanished down the hole, along with most of Mr Bush's bed.
"All I could see was the cable wire running from the TV going down into the hole. I saw a corner of the bed and a corner of the box spring and the frame of the bed," Mr Bush said.
County administrator Mike Merrill described the home as "seriously unstable" and said no one could go inside because experts were afraid of another collapse and losing more lives. The soil around the home was very soft and the sinkhole was expected to grow, he said.