Broome County Judge Martin Smith sentenced 23-year old Shawn Munck this morning to time served, and 5 years probation.
He was found guilty in August of criminally negligent homicide.
Munck told police he stepped on his brother's stomach to pin him down at his grandmother's home in February 2008.
12-year old Peter Munck was discovered dead a few days later.
The Prosecution says Shawn Munck didn't seek medical attention or report the death.
He's been free since the trial in August, after spending a year and a half in jail.
At that time, the jury dismissed other charges of manslaughter and assault.
Judge Smith dismissed a murder charge.