A British aristocrat and her boyfriend were sentenced to 14 years in prison on Monday for killing their newborn daughter while on the run from authorities.

Constance Marten, 38, and her partner Mark Gordon, 51, a convicted sex offender, were found guilty in July of gross negligence manslaughter by London’s Central Criminal Court. They had also been convicted of perverting the course of justice, concealing the birth of a child and child cruelty. Gordon will serve an additional four years on extended licence.