Ashlyn Berry's family ate barbecued chicken for dinner Tuesday night, cooked on a grill that sat on the sidewalk outside her apartment building. After she thought the ashes had cooled, she placed the grill on her balcony and went to sleep.

A few hours later, she heard her 15-month-old son in the next room, wailing and screaming, "Mommy, Mommy."

An ember from the grill had ignited the wooden balcony and their uptown apartment was on fire.

Investigators said 14 other units were damaged and they are trying to figure out whether the building's smoke alarms and sprinkler system work.

The 4 a.m. fire sent Berry's family to the hospital and left 13 people in adjacent apartments homeless.

Berry, who was briefly trapped by the smoke and flames on a third-floor balcony outside her bedroom, was rescued by firefighters who were driving by.

Her son, who has asthma and bronchitis, was hospitalized in intensive care Wednesday, but was expected to recover, Berry said. Her daughter and boyfriend also were briefly hospitalized with injuries that weren't life-threatening.

Berry and other residents say the sprinkler system and smoke alarms never went off.

"The sprinkler system did not work. The alarm system did not work. Nothing worked," she said.

As she talked, firefighters removed charred children's toys and other belongings from her apartment. "...If my son hadn't gotten up and cried, or if I hadn't been able to hear it, we would've been dead."

Others had to be rousted by a resident who ran door-to door.

After the fire started on the balcony, investigators said, it spread to other units via the walls and attic, but was stopped by a fire wall.

The building at Davidson and Ninth streets is owned in part by the Charlotte Housing Authority, which works with people who live in subsidized housing units like Berry's. The Housing Authority was investigating Wednesday.

Calls and messages to Pinnacle Management Services, the company that runs the apartment complex, weren't returned by late Wednesday.

The apartments were built in 1999, and building codes required that the sprinklers be installed, said Deputy Fire Marshal Jonathan Leonard.

According to Deborah Clark, spokeswoman for the Charlotte Housing Authority, Pinnacle Management Services is responsible for making sure the sprinkler system works.

Leonard said it's legal but ill-advised to leave a hot grill on a wooden balcony. People can be cited for cooking on an apartment balcony, he said.

He and other investigators began looking into the sprinkler issue Wednesday afternoon. They have to dig under piles of burned wreckage and Leonard said he couldn't give an estimate of how long it would take investigate claims about the sprinklers.

"We may never know if those sprinklers were activated," he said. Staff writer Steve Lyttle and WCNC-TV contributed.