The children, 4-year old Rolando Rich and his 3-year old sister Desani, are in critical but stable condition at Brookdale Hospital.
The fire broke out in the master bedroom of a second floor apartment in the Van Dyck houses, just after 2:30 a.m. Saturday.
Two older children were able to make it out safely, as did residents from other units, but firefighters had to rescue the two younger children, who were overcome by smoke.
Both were unconscious when they were pulled to safety.
The fire was brought under control within 45 minutes.
The cause is still under investigation.