The baby's father was in critical condition Sunday evening for injuries sustained in the fire. The boy's mother and six other children, ages 1 to 17, also escaped from the home.
The fire broke out at about 2 a.m. in a home in the 1700 block of West 59th Street in the West Englewood neighborhood.
The baby was identified as Treshawn Estes, according to his aunt, Cynthia Estes.
The baby's parents, Samuel (Tony) Estes, 51, and Shamekia Williamson, 37, were married on Saturday. They had a blended family of seven children.
"Here it is his wedding day and they lose their baby and he almost lost his life," Cynthia Estes said.
Police on routine patrol were the first to help, witnesses said. Two officers went inside the home and one broke a window so they could get in, a witness said.
When firefighters arrived, the first floor of the house was engulfed in flames. Fire officials say the fire was accidental and started from a stove.
Samuel Estes sustained cuts, bruises and burns after jumping out of a second floor window to escape the flames.
It was unclear if the home had working smoke detectors.
Relatives say the fire is the latest tragedy to befall them.
Six month ago, they lost their matriarch. Now, with the family home destroyed and with no savings or insurance money to pay for the baby's funeral, they're hoping for a miracle and the kindness of strangers.
"We need help. We need more than just prayer. Whatever you all can do to help we would really appreciate it," said relative Cynthia Taylor.