The mother of a young boy who died after being beaten at a Cranston apartment complex in 2009 has been sentenced to prison.

Trish Oliver, 33, of West Warwick, received a 20-year sentence with eight years and nine months to serve, and the balance suspended with probation, during an appearance in Superior Court on Tuesday.

In May, Oliver pleaded guilty to one count of manslaughter in connection with the October 2009 death of her 6-year-old son, Marco Nieves.

She was indicted in August 2015, a month after her former boyfriend, 34-year-old Michael Patino, was sentenced to life in prison following his conviction on a charge of second-degree murder.

According to authorities, Oliver became aware that her son required medical attention on the afternoon of Oct. 3, 2009, after Patino struck the boy hard enough to tear his intestine and inflicted other injuries.

Authorities say Oliver and Patino found the boy unresponsive and not breathing shortly after 6 a.m. on Oct. 4, 2009, and finally called for help. Emergency personnel responding to Oliver’s apartment at 575 Dyer Ave. found the boy in full cardiac arrest and rushed him to the hospital, where he was pronounced dead 11 hours later.

“Trisha Oliver failed to seek medical treatment for her six-year-old son Marco for more than 15 hours, knowing he was in excruciating pain from blows delivered by her boyfriend, Michael Patino,” Attorney General Peter F. Kilmartin said in a statement announcing the sentence. “It is unconscionable that Trisha Oliver watched her child be in severe distress, and be more concerned about the whereabouts of her marijuana than seeking medical assistance. It took until Marco stopped breathing for Oliver to call 911, and then lied about the severity of her son’s injuries to medical professionals, preventing him from receiving life-saving treatment. Trisha Oliver failed in her most basic duties as a mother by not providing Marco the aid he desperately needed, leading to the unnecessary and tragic death of an innocent six-year-old boy.”

Cranston Detectives John Cardone and Jean-Paul Slaughter led the investigation of Marco’s death. Assistant Attorney General Stephen A. Regine and Special Assistant Attorney General Peter Roklan prosecuted the case.