A Dublin man has been jailed for seven years for killing his stepson in May 2013. 

David Mahon stabbed Dean Fitzpatrick, the son of his now wife, outside his apartment on the Malahide Road following a row over a stolen water bottle.

The pair argued inside the apartment before Mr Mahon followed his stepson out to the landing and pulled a knife from his pocket.

The 23-year-old later died from a 14cm deep stab wound that cut through his main blood vessel.

Mr Mahon admitted holding the knife that killed Mr Fitzpatrick but claimed it was accident, saying the deceased had walked into the blade.

The 45-year-old was cleared of murder last month but convicted of manslaughter. He has been in custody ever since.

The production of the knife and its subsequent disposal were considered as aggravating factors by Ms Justice Margaret Heneghan, while his remorse and co-operation with gardaí were taken into account in his mitigation.

The death is not the first tragedy to befall the family: the victim's sister, Amy, has not been seen since she went missing in Spain in 2008.

The family had moved over there four years beforehand.