A Sebastopol man convicted of killing his older sister in a drunken-driving crash has been sentenced to 10 years in prison.

Chanowk Pendergrass was sentenced Thursday in the May 22, 2016 crash that killed Iiana Abigail Wolfe, 36, a mother of four who was visiting from Virginia. Jurors in January convicted Pendergrass of gross vehicular manslaughter while intoxicated and possession of nitrous oxide, also known as laughing gas.

Prosecutors said Pendergrass, who had been on probation for a previous drunken-driving conviction, was drinking and inhaling laughing gas the night of the crash. He is alleged to have refused offers for an Uber ride home and grabbed his keys back after they were taken away by friends, prosecutors said.

He was driving his sister in his GMC pickup on Llano Road when he failed to make a turn and crashed into a concrete culvert. Evidence suggested he was going 77 mph just before impact.

CHP crash experts testified it was one of the worst crashes they had seen with the engine and transmission of the truck forced into the cab. Wolfe, who went by the name Abby, was killed instantly.

You can reach Staff Writer Paul Payne at 707-568-5312 or paul.payne@pressdemocrat.com. On Twitter @ppayne.