New clues in an 18-year-old incident that left a baby boy dead have led to charges against the infant's father.

The suspect, 39-year-old Gabriel Palumbi appeared in a Valleyfield courtroom Friday to be charged with the 1991 involuntary manslaughter of the boy, in the village of St. Martine, 300 kilometres east of Montreal.

At the time of the incident, paramedics coming to the home found the five-month-old boy was unconscious. He died the next day.

New evidence has established that someone shook the child, causing his brain to move inside his skull, which can now be proven leads to fatal consequences.

"It was a question of determining when, and who was with the baby at the time, and the conclusion was that Mr. Palumbi was alone with the victim at that time," said prosecutor Claude Doire.

Now the father of a teenage son, Palumbi is married to the boy's mother, who had no idea he was a suspect.

"He does have a spouse and a child, that's all the information I have," said defence lawyer Catherine Perron.

Many of Palumbi's relatives appeared in court to support the man.

He returns to court for a bail hearing Thursday.