The son and daughter of former UTV presenter Brian Black who died after his car plunged into Strangford Lough have described his death as "unreal".
Kieron Black and his sister, Sarah Brown said they are "very much in shock" following the death of their 77-year-old father on Tuesday.
The grandfather, who was a familiar face on UTV - initially on the award-winning current affairs programme Counterpoint and then as an environmental correspondent - was in his car when it rolled backwards off the quay in Strangford village at around 11.30am.
Locals ran to the scene and used a hammer to smash a window in the vehicle, which was lying upside down, to free Mr Black, who lived in the Strangford area.
Speaking to the Irish News, Kieron Black said mechanical tests had been carried out on his father's car however a witness reported that the 77-year-old had just gotten out of his vehicle, which then began to move.
It is believed Mr Black got back into the car to try and stop it but it rolled off the quay.
He said his father was at the quay as he was preparing to board his boat to sail to Scotland to visit his daughter, Sarah, who lives in Argyle.
The father-of-one, who lives in Killough and works as a cartoonist, revealed he had spoken to his dad at around 10am.
"His greatest love in life had been seeing his grand-daughter and his family," Kieron said.
"Certainly the attention it has received in the media gives an indication of how well he was known outside of his circle of friends and family.
"He was always a quirky fella, larger than life. He was a journalist to the end. He was busy writing for Yachting Monthly" as well as a number of other publications.
Kieron said his father had just returned from visiting Connemara in his camper van where he went hiking in the mountains.
"He set an example of how to treat the countryside," he said.
"He was forever in the mountains. He was a lovely father, always encouraging the outdoors and love for animals and not leaving any trace of any litter".
Sarah Brown said she and her brother had been "overwhelmed" by the stories they had heard of the efforts to save their father, adding she wanted to say "thank you" to all.
"There were so many people who tried to help him and there have been so many messages coming through," she said.
Sarah said her father, who had sailed to the Artic on his boat a number of times to investigate climate change first hand, "wasn't afraid" to report issues and had taught them to "be the change you want to see".
"That will certainly live on in me," she said.
"It still feels unreal. I am very proud of him and I am proud of how he handled losing mum".
Kieron said it was difficult for the siblings to sit down to write a second eulogy within 10 months, following the loss of their mother, Lesley (76) in September.
"We will never fill that void," he said.
"His legacy for us would be an appreciation of the environment and the physical world.
"I always had a suspicion that the sea would take him because he pushed sailing so hard for so long and in so many destinations and there were so many risks and so many situations he overcame - but just not like that".