A DuPage County man convicted of stabbing his mother to death after she refused to help him get tickets to an Avril Lavigne concert has been sentenced to 40 years in state prison.

A DuPage County man convicted of stabbing his mother to death after she refused to help him get tickets to an Avril Lavigne concert has been sentenced to 40 years in state prison.

The county's state's attorney's office says Judge Kathryn Creswell sentenced 39-year-old Robert Lyons of Carol Stream on Monday.

The sentence comes four months after a jury found Lyons guilty of first-degree murder in the March 2008 slaying of 61-year-old Linda Bolek.

During the trial, prosecutors contended that Lyons became enraged when he found out his mother would not call a friend to get tickets to the concert. The woman's body was found on the kitchen floor of the condo the two shared. Lyons was arrested six hours later at an area Hooters restaurant.