He Promised to Show His 2-Year-Old Daughter Christmas Lights — Instead, He Set Her on Fire. Now, He's Dead in Prison

An Arizona man who was serving a life sentence for pouring gasoline on his two-year-old daughter and setting her on fire has died in prison.

Shawn Ryan Grell, 50, died on April 19 at ASPC-Tucson facility, according to the Arizona Department of Corrections, Rehabilitation and Reentry.

“All inmate deaths are investigated in consultation with the county medical examiner’s office,” the department said.

It’s unclear how the inmate died.

Grell picked up his daughter Kristen Salem from her daycare in Dec. 1999 with a plan to take her to see Christmas lights, the East Valley Tribune reported.

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Instead, the twosome drove to a department store in Mesa where he purchased a gas can and then bought some gas. He then drove to a remote desert area in east Mesa before placing his daughter on the ground and setting her on fire, according to the Tribune.

The girl crawled about 10 feet before she died, prosecutors said, per azfamily.com.

He was convicted of first-degree murder and robbery in connection to her killing in 2001 and sentenced to death.

However in 2013, his death sentence was commuted after the Arizona Supreme Court ruled that he had mental retardation, azfamily.com reported. He was sentenced to life in prison.