A Suffolk man who sexually assaulted his stepdaughter will serve 16 years in prison after being sentenced Monday.

Duwayne Franciscus Eaton was found guilty of two counts of rape of a victim under 13 and one count of rape by force, threat or intimidation, Senior Assistant Commonwealth’s Attorney Marie Walls said.

Walls said Eaton had begun to assault the stepdaughter he had raised since birth when she was 10 years old. Last year, at the age of 17, she reported the abuse to an adult at her school, who contacted Child Protective Services and police.