David Sparks was sentenced to 50 years in prison for killing Savannah Spurlock
Sparks was arrested in July 2019 after the mother-of-four's remains were discovered on a property in rural Garrard County owned by his parents
Spurlock went missing on January 4 after leaving a bar in Lexington with Sparks and two other men; her body was found in a shallow grave six months later
In a Facebook post, Spurlock's family said that investigators are still unsure how she died and why Sparks killed her
Sparks will be eligible for parole after serving 20 years of his sentence