Ibrahim Kibayasi will enter prison "with a heavy heart" and he will remain there for 35 years, said Cook County Judge Hyman Riebman.
Riebman pronounced sentence Monday on the Mount Prospect man convicted in the shaking death of his infant son, Dylan.
Riebman found Kibayasi, 31, guilty of first-degree murder following a four-day bench trial in April during which Kibayasi wiped away tears when he testified that he never intended to harm his son.
"I just lost my mind," he said, describing how he grabbed and shook the crying 5-month-old on Sept. 3, 2009, causing the subdural hematoma which resulted in Dylan's death.
"I accept full responsibility," said Kibayasi, who asked Riebman for mercy. "I loved my son with all my heart. If I could turn back the hands of time and change those few seconds … I would do it."
Defense attorney Robert Callahan said Kibayasi came to the U.S. to attend college, earned an associate degree in accounting and worked two full-time jobs to support Dylan and his mother.
Callahan pointed out to the court that Kibayasi has no criminal background and has support from his family, including his father, a United Nations employee who attended his son's trial.
"This is the one huge mistake which is a tragedy," Callahan said.
Requesting a "significant sentence," prosecutors painted a different portrait of Kibayasi, saying his anger problem and his inability to deal with stress cut short his son's life.
"He had no excuse for what he did. He should have known better," said Cook County Assistant State's Attorney Mike Clarke.
Referring to a 52-minute videotaped police interview in which Kibayasi demonstrated shaking the baby, Riebman agreed with prosecutors that Kibayasi has a problem with anger.
"He had issues with regard to employment which appeared to be what triggered his anxiety," Riebman said.
But while Riebman considered Kibayasi's clean record and remorse, he also considered the violent nature of Dylan's death, the fact that Kibayasi was in a position of trust, and the need for the sentence to serve as punishment and as a deterrent to others.
"The bottom line in this case is the defendant as a father has one job, that is to protect, nurture and raise his child to have a happy, healthy life," Riebman said.
He failed to do so, Riebman said.
"For that moment in time, Mr. Kibayasi lost the ability to recognize the humanness of Dylan," he said.
Kibayasi received credit for the 681 days he has been in custody since his arrest. He must complete 100 percent of his sentence before he is eligible for parole.