Edgrekia Blackmon was taken to a Lansing hospital Thursday night before being transferred Friday to a Grand Rapids hospital where she had surgery, family members said.
"We were out here having a blast, it was just family," said her cousin, Dennis Patrick. "She bent down to light the fuse and it exploded in her face. She then fell back, her Detroit Pistons jersey was on fire, and she put herself out."
An emergency crew found Blackmon on the ground but conscious.
"She lit it correctly. She had it in a clear area, she was standing to the side of the device, and something went horribly wrong," said Steve Babcock, spokesman for the Lansing Fire Department.
Meanwhile, in Sterling Heights, north of Detroit, five people were hurt when fireworks ignited in a street went awry. A mortar tipped over and shot into a garage.
Police said the man who set up the fireworks was ticketed. The injured included two 8-year-old girls.