The second member of a Chicago firefighter’s family has died after a fire broke out at their Montclare home on Tuesday night.

The firefighter’s wife, identified as 36-year-old Summer Day-Stewart, according to the Cook County Medical Examiner’s Office, died on Thursday at 7:30 p.m., PEOPLE confirms.

Although no updates have been provided on the couple’s other two children, 2 and 7, Chicago fire officials said on Thursday they remained in “extremely critical condition” and had been unconscious since the fire, reported theChicago Sun-Times.

Afterwards, the mother and her three children, who all “suffered smoke inhalation” were “transported to various hospitals in critical condition,” police said at the time.

According to the fire officials, their homedid have smoke detectors.

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Although Walter Stewart, also an EMT, was not assigned to respond, he performed CPR on his wife after arriving at their home, fire department spokesperson Larry Langford told theSun-Times.

The investigation into the fire, still undetermined, was suspended on Friday, Langford told theChicago Tribune, adding that it’s possible investigators will do a forensic analysis later.

A fire department spokesperson previously told PEOPLE that preliminary information indicated that the fire began in the kitchen.

Speaking with theChicago Tribune, Langford said the department is “doing all we can to support him.”

“It’s just unbelievable,” he added. “I can’t even think of what it feels like.”

The Chicago Fire Fighters Union Local 2, which iscollecting money for the family, has also pledged their “ongoing support” to the family.

source: people.com