Valeliano Mita and his young son were fishing at a Wellington wharf when a gust of wind suddenly whipped up and pushed the boy into the water below.
The 40-year-old father of three did not know how to swim but did not hesitate to jump into the sea to save his eldest child, 8-year-old Matelagi.
Mita's brother, Sylvester Nansen, has described the harrowing moment a week after the tragedy at Seatoun Wharf, about 8.35pm.
"They were out fishing and the wind pushed his son into the sea. He went in and saved him," Nansen said.
"We can only say thank you to the people who tried to help him that day because the only best thing is that he's gone, but his son has survived - and that's all Valeli wanted that day."
MetService said winds in Wellington last Saturday were moderate, with gusts of up to 26km/h recorded near the airport.
Past weather conditions recorded by the Time and Date website have wind gusts of up to 42km/h between 6pm to midnight, however.
Mita had lived and worked in Wellington for about 10 years after arriving in the country via the Samoan Quota ballot.
He worked at a waste management company during that time; supporting his wife, Merita, and their children as well as sending money home for his mother, Telesia.
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Merita and the children arrived in New Zealand only in the last few years and had set their young family up here with big dreams.
"They were all there [at the wharf] that day, but she was looking after the younger children - their little daughter and other son."
Nansen paid tribute to a brother, the eldest of four siblings, who was known for his humility and quiet nature.
"He was always silent. He wasn't the type to talk back.
"It wasn't easy news to hear and it was very hard to tell our mother."
It is understood a flotation device will soon be installed at Seatoun Wharf as a result of the tragedy, Newshub reported.
Mita's family are now working to get to New Zealand for his funeral services, which are due to take place in Auckland on Tuesday.
Up to 10 family members were due to touch down in Auckland today, but flights from the Samoa have been cancelled today due to Tropical Cyclone Tino.
Drowning death toll now 8
Mita is one of eight people who have died by drowning since the start of this year.
The figure was true as of yesterday, according to Water Safety New Zealand, with lives lost at beaches, lakes, rivers and harbours around the country.
The youngest victim on that list was 11-year-old Joshua Southon, who died alongside his father Darren Southon, 48, while they were snorkelling for kaimoana off the Wairarapa coast on Friday, January 10.
Louis Solofua, also known as Lusi, was the 59-year-old kayaker who went missing last Saturday morning after going out to check fishing nets at Lake Ellesmere/Te Waihora.
His kayak was found about 2.30pm the same day - about two hours after the alarm was raised. His body was recovered on Thursday.
On Monday, just before 8.30pm, Kristi Ann McIntyre was pulled out of the water in a critical condition at Oakura Beach in Taranaki.
Surf Life Saving NZ said she and a man, understood to be her husband, had gone for a swim near a campground about 7.45pm when they got into trouble.
A surfer and a group of off-duty lifeguards got the pair to shore, before doing CPR on McIntyre, but to no avail.
On Wednesday, in Auckland, three boaties found themselves in a nightmare situation when their boat capsized near Manukau Heads.
The alarm was raised just after 9pm. Police said later that the group had been in the water for "a number of hours".
Despite all making it to shore, one of the men - aged between 55 and 64 - died at the scene.
Two other men have died since the start of the year, according to Water Safety New Zealand.
Chief executive Jonty Mills said it was important to remember that although the water was a playground, it was also very unpredictable at times.
"We've still got a couple of months of summer and we want everybody to enjoy the water ... but we just want them to come home safely to the whānau.''