Regardless of what happens next in sentencing, one thing is certain; Logan Mott will serve time for the murder of his grandmother Kristina French.

The first day of Mott's sentencing on Wednesday took a deep dive into the life of the teenager who pleaded guilty to killing his grandmother and burying her in the backyard of his father's Neptune Beach home in November 2017.

Two key witnesses took the stand Wednesday including the lead Jacksonville Sheriff's Office detective in the case, Neil Chandler, and Mott's father Eric Mott.

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During his testimony, Chandler told the court that JSO's investigation revealed Mott had been part of a chat group on Instagram in which other teens told him how to clean up the crime scene and hide the body.

"The evidence, to me, suggests that there was a level of premeditation, that her death was violent, it did not have to happen and there was a great deal to cover up that death," Chandler said. 

Meanwhile, Eric Mott maintained that his son had a good relationship with French, who is Eric's mother. Eric Mott, who is a Jacksonville Corrections Lieutenant, gave an emotional testimony.

"She enjoyed being the grandparent and always being the good person," Eric Mott said. "And just spoiling Logan. She just liked being a grandma. And Logan- their relationship was great."

Eric Mott said Logan had been seeing a therapist, while also describing a contentious marriage to Logan's mother that was marked by allegations of domestic violence and child neglect investigations.

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Mott is due back in court at 11 a.m. Thursday at the Duval County Courthouse.