Visibly intoxicated in the early morning of March 4, Mia S. Marshman struggled to recall whether all three of her children made it out of her burning Larimer home, police said.

Police asked her several times if she had another child in addition to the two that had escaped, but she was unresponsive, according to a criminal complaint filed against her yesterday.

Finally, a passer-by from the neighborhood informed authorities she did have a third child, according to the complaint.

Firefighters found 6-year-old Isaiah Marshman in a room on the second floor, trapped by thick black smoke. Isaiah was in cardiac arrest when paramedics started treating him, according to a police department news release.

He died less than an hour later, at 3:45 a.m., in UPMC Mercy.

Police charged Ms. Marshman yesterday with involuntary manslaughter and endangering the welfare of children in connection with his death.

At the scene of the fire on the 6400 block of Winslow Street, Ms. Marshman told police she started it while cooking after she "drank a lot of alcohol and had some weed," according to the complaint.

Arson investigators later determined the blaze began in the first floor kitchen because a pot of grease was left unattended and overheated, police said.

Ms. Marshman initially consented to a blood alcohol test, but then refused when she arrived at UPMC Presbyterian, according to the complaint. Police obtained a warrant for her blood, and it tested positive for marijuana and her blood alcohol content was 0.268, more than three times the legal limit to drive, according to the complaint.

Ms. Marshman's daughter, 2-year-old Keiyonna Trowery, was taken to Children's Hospital in stable condition. Her 8-month-old son, Javon Marshman, was also taken there as a precaution.

Firefighters responded to the blaze around 2:45 a.m. and found Ms. Marshman inside with her infant boy. Keiyonna was later rescued from a second-floor bedroom. Firefighters had the two-alarm fire under control by 3:20 a.m.

Homicide detectives arrested Ms. Marshman at 8:45 a.m. yesterday. She was awaiting arraignment last night.