Updated

The off-duty firefighters and neighbors who helped pull a 4-year-old boy from a burning SUV deserve more gratitude than words can express, the boy's father said Tuesday.

Firefighters Joel and John Rechlitz, who suffered burns to their hands and forearms, are among the brave Milwaukee citizens who have the family's deepest gratitude, James Harper said.

"I just want to thank everybody, the citizens of Milwaukee, for helping us," Harper said during brief remarks at a news conference. "There are angels all around us."

The Rechlitz brothers, along with neighbors and off-duty police Lt. Mark Wroblewski, sprang into action Sunday after the SUV slammed into a tree in a Milwaukee neighborhood and burst into flames.

In a scene caught on amateur video, about a dozen people converged to help save the driver and her 2-year-old daughter. But 4-year-old David Harper remained trapped in his car seat behind a wall of flames.

The firefighters, who had been directed to the scene by phone calls from their wives, used a knife to cut the car seat's restraints and pull the boy to safety.

David, whose family calls him D.J., was upgraded to serious condition but stable Tuesday morning at Children's Hospital of Wisconsin, in the Milwaukee suburb of Wauwatosa.

D.J. had burns — many deep enough to be considered third-degree — over 20 percent of his body, pediatric surgeon David Gourlay said. The burns covered most of his scalp, his upper back and upper extremities, with less severe burns on his face.

"I believe D.J. will make a full recovery," Gourlay said. "What's challenging with burns, especially deep burns that are extensive like D.J.'s, is the functional, the cosmetic and the psychological recovery from that."

The boy was sedated and would need months of skin grafts and physical therapy, Gourlay said.

Police continued to investigate the crash.

The SUV was driven by Harper's wife, Angela Baldessari, 32, of Kingsport, Tenn. Witnesses said the vehicle swerved, struck a tree and immediately caught fire.

Jason Lepkowski told Fox News that he was driving behind Baldessari when he saw her crash.

"I looked up and she was already flipped over and blown up," he said. "The car was on fire before I could even get out of my car."

Amid plumes of thick black smoke, Baldessari handed her 2-year-old daughter, Beverly Harper, to bystanders through the top of the SUV. Baldessari then escaped through the windshield after others smashed it open.

D.J. Harper was still trapped.

The Rechlitz brothers took turns reaching for him through the windshield, but were repelled by heat and flames.

Wroblewski, the police lieutenant, arrived with two fire extinguishers, and he and Joel Rechlitz tried to hold back the flames. The extinguishers bought valuable time, Joel Rechlitz said.

"Five, 10 seconds made the difference between this boy living and this boy dying," he said.