The following night, at about 9pm, Kaea jnr went to his father's house in the hope of finding him.
He discovered he wasn't there so waited about an hour before leaving and heading to his sister's house in Kihikihi.
Kaea jnr woke early on the morning of December 15, and drove his silver Subaru to his father's partner's house in Hazelmere Cres about 4.30am.
After he arrived, his partner's dogs began barking and unable to see if his dad was there, he left.
He returned again about 6am, armed with a 595gm claw hammer.
Kaea jnr walked to the back of the partner's house, and calmed the dogs down before climbing through an open window.
He then walked through the house where he saw someone asleep on the couch.
Confirming it was his father, he then struck him on the back of the head five times with the hammer.
The noise of the blows woke his partner and she yelled at Kaea jnr to get out.
Startled, Kaea jnr fled the scene, while Kaea snr's partner called an ambulance.
Kaea jnr drove north on State Highway 3, throwing the claw hammer out the window as he crossed the Mangapiko Stream, heading to an associate's house before ending up at his sister's house.
Kaea jnr was soon after contacted about the death of his 48-year-old father by his mother, and about 1pm drove to his mother's house with whānau as they waited for police to arrive.
Justice Timothy Brewer sentenced Kaea jnr to life imprisonment with a minimum non-parole period (MPI) of 11 years and six months.
'Predatory and pre-meditated'
Crown prosecutor Jacinda Hamilton said Kaea jnr's offending could be properly characterised as "predatory and pre-meditated".
"This was a planned killing in which the defendant undertook a determined search to locate him.
"That was followed by the unlawful entry of his home and sustained attack with a weapon against a person who was asleep and utterly defenceless."
She urged the judge arrive at an MPI of 13 years, taking into account his age and previous good record.
Defence counsel Ted Walsh pushed for a 10-year MPI, suggesting further discount be offered given the contents of a Section 27 report.
His client was remorseful and he wanted to get the message across to the packed public gallery of whānau.
'Killing father 'surreal''
Justice Timothy Brewer accepted Kaea jnr was seeking retribution "but that desire for retribution can not excuse your offending".
He also accepted he was genuinely remorseful and had strong prospects for rehabilitation.
"You feel sorry for killing your father and are ready to face any sentencing [today].
"You hope your whānau will forgive you one day."
A Section 27 cultural report found that Kaea jnr had mostly enjoyed school, despite issues with bullying.
He struggled with the company of others and felt it was easier to be alone than talk with others.
After leaving school he gained a certificate in building and construction but was unemployed at the time of the murder.
Kaea jnr told a pre-sentence report writer killing his father had felt "surreal" and understood if he had sought help sooner for his anger, he would still be alive.
"You were surprised that you remained as angry as you did for so long because you did not believe that you were an angry person."
Justice Brewer said the murder appeared to have happened "out of an extreme over-reaction".
