DOTHAN, Ala (WDHN)— Nearly four years after the death of his three-month-old son, a Dothan father has pleaded guilty to capital murder and faces a 20-year prison sentence.

Rolando Castillo Jr, 35, of Dothan, has pleaded guilty to a charge of capital murder and will serve 20 years in a state penitentiary.

Castillo was scheduled for an October 24 court date before he entered the plea agreement.

Karen Nolen, the grandmother of Desmond Castillo believes the sentencing for her grandson is a little lenient for the crime.

“I’m glad that he admitted that he had done it the sentence was shocking he should have at least got life Desmond got the death penalty at three months old,” Nolen said.

According to DPD, in January 2018, officers responded to a report of an infant not breathing. When officers arrived on the scene, they found the parents performing CPR on the infant, Desmond Castillo.

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Desmond was transported to Flowers Hospital, where he died.

In April 2018, investigators say they received the results of the autopsy performed by the Alabama Department of Forensics, and various internal injuries were revealed. The cause of death was determined to be blunt force trauma to the head and torso.

“The time I got to the hospital he was gone. I saw Desmond come into this world and I saw Desmond leave the world,” His grandmother said.

The autopsy came back from medical examiners that Desmond Castillo died from blunt trauma to the head and torso.

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During exclusive interviews four years after 2018 in March, WDHN spoke to both the grandmother and her daughter, Carla the mother of Desmond Castillo.

Although the father, Rolando, was arrested in April of that year, the family was still unsure about who killed Desmond.

“This is not about my daughter, or me, or about Roland this is about Desmond we need to know what happened to that baby and now the truth has come out,” She said.

Nolen says overall it’s a tragedy for their family and it’s not a day goes by that she doesn’t think about her grandson and she will continue to remember him by passing out stickers and signs as she has done for the past four years.

The sentencing hasn’t been determined yet.