A man who gave his son the gun used to kill two students and two teachers at Appalachee High School in Georgia is set to be sentenced Thursday after he was convicted of second-degree murder and involuntary manslaughter. A jury in March found Colin Gray guilty of second-degree murder in the deaths of two 14-year-old students, Mason Schermerhorn and Christian Angulo. Georgia law defines second-degree murder as causing the death of a child by committing the crime of cruelty to children. Prosecutors have said that Colin Gray gave his son the rifle as a Christmas gift and also bought him ammunition, a gun sight and other shooting accessories. Second-degree murder is punishable by at least 10 but no more than 30 years in prison, while involuntary manslaughter carries a penalty of one to 10 years in prison.