39-year-old Robert Lyons of suburban Chicago was sentenced to 40 years in prison today for killing his mother. He killed her because of a disagreement about Avril Lavigne tickets.

Back in 2008, things got complicated between Lyons and his 61-year-old mother, Linda Bolek, because she wouldn't call a friend to get skybox tickets to an Avril Lavigne show for him. Lyons responded by stabbing his mother in the back nine times with two different knives, breaking the blade off one and bending the other.

It got worse. Lyons doused his mother's body with chemicals such as Tile-X, Drain-O and Raid before fleeing the scene to go shopping. Police found him several hours later, chilling at a Hooters.

Lyons has dealt with serious psychological and anger issues since his teenage days. Probably, this is an understatement.

Avril Lavigne has not commented.

[via The Chicago Sun Times]

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