Sister Natahsa Arden told Fairfax: "I'm angry. We're like: 'Stupid Jared. What were you thinking?'
"It's too soon to go that early in life.
"They thought: 'She'll be right, mate'. Good old Kiwi attitude - no lifejackets, blowup dinghy, going for the sea,'' she said.
"It started out as fun.''
Arden revealed her brother had had a sight issue that sometimes meant he needed help from others.
"Most of the time we always had to arm and arm Jared around the place ... we always looked after him.
"Unfortunately we weren't there this time.''
She said it was an emotional time for the family, given they had not got their brother and son back.
"I just wish he would surface. It's an unusual feeling,'' she told Fairfax.
"We want to get on with it, but we can't. Nothing is in our control.''
Family and friends of the men have also paid tribute to their loved ones via social media.
Ryan Wenlick, a close friend of Anderson's, shared a photo of his mate enjoying a beer and paid tribute to his "brother".
"RIP my friend and brother. God knows I'll see you on the other side.''
Just last week, Anderson wished his mate a happy birthday.
Another said news of the tragedy had not sunk in yet.
"RIP my friend Jared Anderson. You will be missed so much," she wrote.
"I'm gonna miss his crazy antics and the nick [sic] names he would give me."
Family members of the 35-year-old said the accident was "such sad news'' and they hoped their loved one would be found soon.
The De Bruyn family are preparing for his funeral to be held over the next few days.
Many of his friends expressed their shock at the news, paying tribute to a good man.
Leanne Allen wrote: "RIP Wayne De Bruyn. Another mate gone ... very sad to hear.''
A limited search of the shoreline will continue at low tide for the next few days, with the use of 4-wheel drive vehicles, to try to locate Anderson's body.