The fire broke out along the 4300 block of Griscom Street just before 2 a.m. and quickly spread to the second floor.
An 8-year-old boy was taken to St. Christopher's Hospital, where he is in critical condition.
A 7-month-old boy was also taken to St. Christopher's Hospital and was placed in stable condition.
A 25-year-old woman was taken to St. Christopher's Hospital by police and placed in stable condition.
A 26-year-old man was taken to Temple University Hospital where he was placed in critical condition.
The fire marshal was called to the scene to investigate.
The man who was injured in this fire was originally said to be 35 years old, but we've since learned he is 26. This story has been updated.