EDWARDSVILLE • A 23-year-old Madison County man continued to proclaim his innocence and pleaded for mercy before he was sentenced Friday to 35 years in prison for the murder of his 3-month-old son.

Under Illinois law, Donald R. Miller must serve 100 percent of the prison term. He was sentenced by Associate Judge Kyle Napp.

A jury in April deliberated about two hours before finding Miller guilty of first-degree murder in the October death of Ashton Miller in a home near Granite City that Donald Miller shared with his girlfriend, Heather N. Smith.

A pathologist testified during the trial that the baby had suffered numerous other injuries at the hands of another person or people before dying of suffocation.

Smith, 21, blamed Miller and testified that he was angry because the baby was crying. Prosecutors dismissed a murder charge against her, and she was sentenced last week to 10 years in prison after pleading guilty of aggravated battery. She must serve 85 percent of that term.

Miller told the judge he was a terrible father who put his addiction to heroin before the welfare of his two children. But he insisted he did not kill Ashton.

"I wasn't a good father, but I loved my son with all my heart," he said. "Please don't make me lose my daughter. ... Don't take away my life. I did not kill my son." Miller said he could not blame Smith for the baby's death because he didn't know what happened.

Napp told Miller he and Smith "did not deserve to be parents." She said Ashton died because of their selfishness.

During the sentencing hearing, Miller, his mother and older sister testified that he was constantly in trouble when growing up and was treated for attention deficit disorder.

Miller said he first used cocaine when he was 12 and went on to use methamphetamine, narcotic painkillers and finally heroin.

Prosecutors asked for a 70-year sentence, but Miller's attorneys asked for 20 years. The sentencing range was 20 to 60 years, or up to 100 years under an enhanced sentence provision for the murder of a child.