A military contractor was sentenced to 45 years in federal prison for enticing his live-in girlfriend to have sex with her 10-year-old son.

Casey Carson, 27, was sentenced Monday in U.S. District Court, six months after he pleaded guilty to conspiracy to transport a child in interstate commerce for illegal sexual activity and traveling in interstate commerce to engage in illicit sexual conduct with a child.

The government said that Carson, who lists addresses of Fairview Heights and Dellroy, Ohio, told the child's mother he was interested in watching her have sex with her son, and that she and her son would have a closer relationship if they were intimate.

Between August 2005 and February 2006, Carson and the mother twice brought the child — who didn't live with her full-time — from the child's home in Missouri to Illinois for visitation, during which the boy was forced to have sex with his mother, according to the criminal complaint.

Photographs of the sexual conduct were taken, with Carson directing the boy as the sex took place.

When Carson was arrested last September at Detroit International Airport, he was a military contractor on a home visit from Kuwait. After his release from prison, Carson will be on parole for the rest of his life.

The mother, identified in court papers only as "B.R.," has not been charged.

Telephone messages left Tuesday with the U.S. Attorney's Office were not immediately returned.