Julio Carrillo's sister comes to his defense Tuesday night.
He was arrested Monday after the death of his two-month-old baby.
Carrillo now faces a charge of felony neglect.
Alejandra Carrillo says her brother did not kill his baby boy.
"He loved him a lot," said Carrillo.
On Monday, police responded to the 100 block of East Pontiac Street after relatives called 911, saying a baby stopped breathing.
Medics rushed the child to the hospital, but he did not survive.
One day later, police handcuffed the boy's father, 19-year-old Julio Carrillo.
Court documents say Carrillo told police he spanked the fussy infant then tripped and fell, causing the baby to hit his head on the floor.
Julian(ABC21 Reporter): " You feel like people are calling him a monster?
Carrillo: "Yea, and it's not true. He loved his baby more than he loved anybody.
Julian: "He admitted in the police report to spanking the baby. What do you have to say about that?
Carrillo: "I don't know. Probably he was frustrated, I really don't know what happened. But I know he wouldn't do anything that extreme to actually kill him."
Court documents quote a doctor as saying the infant had multiple brain bleeds, a depressed skull fracture, bleeding tears to his rectum, and bruises covering his rear end.
Carrillo maintains her brother was an awesome father.
"He would feed him, change his diaper, play with him, always taking pictures with him," said Alejandra Carrillo.