HAVRE (AP) — A Rocky Boy man was sentenced Friday to more than 13 years in prison for his role in the death of his 11-month-old son.

U.S. District Judge Brian Morris sentenced Garrett “Kirby” LaFromboise during a hearing in Great Falls.

LaFromboise, 21, and his girlfriend, Cecelia Rose Gardipee, were charged with second-degree murder and assault resulting in serious bodily injury or aiding and abetting those charges in the Oct. 21 death of Kaidynce Small.

LaFromboise pleaded guilty to the assault charge on Jan. 21 in an agreement that called for dismissal of the murder charge. He also is required to help in the prosecution of Gardipee, who has pleaded not guilty. He will be on four years of supervised release after he completes his prison term.

LaFromboise said he stuck his fingers down his son’s throat and struck him because he wouldn’t stop crying, but that he didn’t cause the boy’s death.

The medical examiner said Kaidynce suffered skull and rib fractures, bruising on his lips, face and torso, cuts on his fingertips and bleeding and bruising on his brain and spinal nerves, but an autopsy did not determine his precise cause of death.

Prosecutors sought a minimum of 10 years in prison, while defense attorneys said defendants convicted of similar crimes have been sentenced to about three years. LaFromboise’s mother sought a probationary sentence with drug treatment while Kaidynce’s mother, Jasmine Small, said he should be imprisoned for life.

“Nobody ever has the right to take a life,” Small wrote. “Why shouldn’t they be imprisoned for life for what they did?”

Kaidynce was in the care of LaFromboise and Gardipee the night of his death under a custody arrangement with Small.

Court records said LaFromboise and Small had a relationship, resulting in the birth of Kaidynce, while LaFromboise and Gardipee were split up.

By the time Kaidynce was born, LaFromboise and Gardipee were back together again. LaFromboise and Gardipee have two daughters together. A paternity test showed LaFromboise was Kaidynce’s father.

“The brutal attack on (Kaidynce) was provoked because LaFromboise could not comfort his own crying son,” the government’s sentencing memorandum said. “Instead of showing compassion to a crying baby, LaFromboise and Gardipee, who were fueled by alcohol, became angry. LaFromboise lost all ability to control his own actions and the situation, the violence spiraled out of control.”