"I should have known better."
Karl, who delivered a eulogy, described Justin as loving, kind, loyal, patient, funny, modest, brave and "the embodiment of goodness".
Although he was well-known, Justin wasn't overly comfortable with the limelight, and was happiest at home with family, cooking, pottering in the garden and making alterations to the house.
Justin, who had a strong Catholic faith, was also fastidious in everything he did.
"Our brother Paul remembers Justin once taking great care to place a pair of long pants under his mattress overnight so they would be neatly pressed when the family went to Sunday mass in the morning.
"What he failed to take into account was the wire-wove base under the mattress - every strand of which was imprinted in his trousers."
Born in Hawera on November 17, 1941, Justin was one of six children to Kathrin and Eric du Fresne.
He had an enjoyable upbringing marred only by two traumatic experiences - severe asthma which one time led to 13 weeks off school, and being present at the death of his oldest brother Peter who failed to surface from a sea dive in the Hawke's Bay.
"The remarkable thing about these adverse experiences is that Justin never showed a moment's self pity or bitterness," Karl said.
"It wasn't in his nature to feel sorry for himself.
"He put bad things behind him, concentrated on the positives, and got on with life."
A possible teaching career was quickly ditched in favour of a radio career when he got a job in Wellington as a clerical cadet at the New Zealand Broadcasting Service but soon, in 1961, became an announcer on 2ZB and then two years later, aged 22, was picked to launch the Sunset Show, where he got to play pop music for 90 minutes five evenings a week.
In the mid 1960s he went to Britain with a singing group called the Folkestone Three, and married Lynn, who had followed him to England from New Zealand. They had two sons, Piers and Andre.
Back in New Zealand, Justin resumed his broadcasting career and was one of the judges in the 1970s television talent show New Faces.
"One of the acts he was called on to judge was an eccentric young band called Split Enz," Karl said.
After working for his father-in-law in the knitwear industry in Levin, and with his marriage ended, Justin opened a menswear store in Waipukurau.
By 1979 he got married a second time, to Judy, and they had a son Christian. Justin also adopted Judy's children Lee and Jenny from her first marriage.
Justin and Jude celebrated their 37th wedding anniversary this year.
In 1983 Justin was invited to Wellington to take part in a special broadcast to mark the 20th anniversary of the Sunset Show.
An overwhelming warm audience response led Radio New Zealand, which owned the commercial network at that time, to offer him a fulltime job.
So after a break of 15 years, Justin was back on air, starting off as an afternoon music host and then becoming a Newstalk ZB Monday to Friday morning talk show host which he presented for 23 years.
"He brought the same easy, affable manner to talkback that he'd displayed on his music show and was rewarded with a devoted following," Karl said.
Winding down his career, he continued doing a Saturday morning show, and by the time he retired in 2013, aged 72, Justin had "established some sort of record for longevity in the fickle world of radio".
"I'm proud of my brother Justin," Karl said.
"I was proud of him when he was a kid and he was a big name on the radio, and I'm every bit as proud of him now."
