A mother whose son was beaten to death by his father is speaking out today after the man was sentenced to prison for manslaughter.

Allisan Tucker only got to spend three years with her son Matthew before his tragic death and today she told CTV News her former partner is a monster who deserves to spend the rest of his life in prison.

But that's not what the court decided.

James Peter-Paul, 29, of Indian Brook, Nova Scotia was sentenced to eight years in prison after he pleaded guilty to manslaughter yesterday in Shubenacadie provincial court.

Tucker says that sentence is not enough considering what happened to their three-year-old son.

"I think it's a joke," Tucker tells CTV News. "I don't think it's justice for my son. I think that by the time Jaime gets out, he might not even be 40. My son didn't live to see four."

Peter-Paul was originally charged with second-degree murder in the death of his son but yesterday he pleaded guilty to a lesser charge of manslaughter.

He was home with his son, Matthew Peter-Paul, on the Indian Brook First Nation on the night of Oct 1. 2010. The court heard that police responded to a 911 call at the residence shortly after 11:30 p.m. that night.

When they arrived, police found Matthew was unresponsive and he was rushed to the Colchester Regional Hospital where he died the next morning.

The court also heard that the boy suffered blunt force trauma to his head, a fractured leg and his head, face and body were covered in bruises.

The cause of death was a ruptured pancreas caused by blunt force trauma to the abdominal wall.

"I think he's a monster," Tucker tells CTV News. "I think it's the most horrible thing I've ever heard. I hate him."

Peter-Paul admits he caused the injuries that lead to his son's death but he says he never intended to kill the toddler.

His guilty plea means there will be no trial. He was sentenced to prison after entering his plea, but Tucker says she wishes there had been a trial.

"I feel like avoiding the trial was to avoid us finding out even more details."

Tucker says social services took Matthew from her and Peter-Paul when he was just five weeks old but she got him back a few days later, on the condition that he wouldn't see his father.

She says Matthew was living with her at the time of the assault, but he went to stay with his father while she attended a business meeting in Toronto.

Tucker says she thought Peter-Paul had changed and she had no reason to believe anything bad would happen to Matthew.

"I went there overnight and saw their house and their family and how they were," she says. "Matthew was so happy there, everything seemed really good there."

"It physically pains me and my family and it's something that, 15 months later, I still feel that way so I don't feel like it's ever going to leave."

Matthew's family is planning to hold a memorial service for him in April, around the time of what would have been his fifth birthday.

As for Peter-Paul, he will spend eight years in prison, minus the 89 days he has already spent in custody.

With files from CTV Atlantic's Kayla Hounsell