A 24-year-old man who stabbed a drug dealer to death over a €100 debt has been jailed for four years.

William Gilsenan was convicted of the manslaughter in October 2014 of 29-year-old Edward Fitzgerald in a car parked outside his home at The Green, Larch Hill, in Santry in Dublin.

Gilsenan pulled out a knife and Mr Fitzgerald died after he was stabbed in the leg and the heart.

Mr Fitzgerald's sister said in a victim impact statement that the family had just buried their grandmother that morning when they heard her brother had been stabbed.

Nicola O'Dea said their lives changed forever and that no words could describe their loss.

Gilsenan apologised to the family saying how sorry he was and that he would never be able to live this down.

The father of two young children said he had destroyed a family and due to his shame he would never be able to look in their faces.

He said he was prepared to take responsibility for what he had done.

Mr Justice Paul Butler said today it was clear the Fitzgerald family had suffered.

The judge said he accepted the jury's finding that the killing was not deliberate and sentenced Gilsenan to six years in prison with two suspended.