23-year-old Zackery Alexander is facing life in prison for the murder of 2-year-old Joseph Bankston in 2015, according to court records.
Monday, Alexander entered the guilty plea waiving his right to a jury trial or an appeal.
He was sentenced to life in prison without parole, plus 66 years.
The toddler’s stepfather, David Wi, who was a Fort Campbell soldier at the time, was also arrested after police discovered he and Alexander had reportedly conspired to commit the crime.
Police said Wi hired Alexander in a plan to kill not only Bankston, but also Brandon Jiminez, Lilly Wi, and Alicia Bankston Wi.
Wi was later sentenced to life in prison, plus 50 years.
At the time of the incident, Wi was reportedly involved in a custody battle with his wife and listed as the beneficiary of life insurance policies on his her, his daughter, and 2-year-old Joseph.