Chicago, Illinois - In a nightmarish scenario, three young children were trapped on the third floor of a burning Chicago apartment Wednesday night, with no sign of their mother or any other adult, the New York Post reported.

It was not yet known on Thursday evening why the fire had broken out, but it was clear who the heroine was that night: the eight-year-old sister.

The little girl had the presence of mind to grab a mattress in the burning apartment and throw it out the window.

The eight-year-old summoned all her courage and jumped. Fortunately, the child did not miss the mattress and was able to escape to safety.

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But the little girl was not finished yet and immediately began trying to save her brothers.

With a lot of persuasion, she got the older of the two to jump out of the window. Miraculously, the four-year-old also landed safely on the mattress.

Now it was also a matter of somehow getting the two-year-old boy to follow his siblings. Luckily, firefighters arrived at the last second and rescued the boy before he put his life in danger by jumping.

Then the little heroes were taken to the hospital for mild smoke inhalation.

"I’m thinking, damn, these kids are smart," District Fire Chief Frank Velez told the Chicago Tribune. "I wouldn’t recommend it, but the fact of the matter is that the kid was quite innovative to think of something," Velez said of the brilliant idea.

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But why were the kids home alone in the first place? According to Velez, their mother had been at work, and a neighbor should have been supervising the three children during that time.

But the man was not on the scene when the flames made their way into the apartment.

No charges have been filed against the mother, a Chicago police spokesperson said.