The identical twin brother of a man at the centre of a video where a baby is being fed vodka says it's ruining his business and affecting his mental health.

Mana Fifita today told the Herald he realises the impact it will have on his brother in speaking out but says it's "all part of the consequences".

The situation has escalated to the point where police and Oranga Tamariki are making inquiries into the video which shows Mana's brother sitting next to a baby as someone else puts a bottle of Long White pre-mixed vodka to its mouth.

The video, which has since gone viral after being posted at the weekend, has also drawn large scale condemnation from social media users.

Detective Senior Sergeant Eddie Sutherland yesterday confirmed police were making inquiries in association with Oranga Tamariki.

The Ministry of Health's Deputy Director of Public Health, Dr Harriette Carr, earlier said they were "appalled" to hear of the video.

There is also a separate photo of the father holding a glass full of beer to his young baby's mouth.

But Mana Fifita decided to speak out today when contacted by the Herald saying he's upset with his brother being caught up in the debacle.

However, he said his brother felt incredibly guilty for what happened and getting everybody caught up in the fall-out.

"When the video was first posted on Facebook I woke up and gave him a call because I already had a lot of people send me messages saying 'people think that it was you'.

"When I rang my twin he felt really bad because on the video it wasn't him that was doing it, it was two of his friends were doing it, one was recording, one was pretending to feed the baby with the alcohol."

An old photo from Mana's brother's Instagram had also surfaced of him pretending to give his baby daughter a glass of beer.

"I know it's only for social media but it's not a good image at all. It's all come from alcohol and that's something that I have been talking to him about."

Mana said he wasn't a big drinker, but did enjoy a beer or wine with dinner or on a special occasion.

He said being identical twins meant people were getting him confused with his Auckland-based brother, with many leaving abusive messages on the social media pages of his tattoo business.

Mana Fifita says the backlash from the post involving his brother has affected not only his business but also his ability to train properly at the gym. (Photo / Supplied)

They looked so alike that even the police had mistaken the pair - he had a visit from two detectives yesterday wanting to question him about the video and look at his tattoos.

"Two detectives knock on my door yesterday and they assumed it was me. They had their file and had photos and I said to them that I have an identical twin and they were shocked because they didn't think this person would have an identical twin and of course they look at the tattoos and take photos of my tattoo and made me write a statement."

He spoke to his brother last night who said Oranga Tamariki staff had visited the home of his partner and four children yesterday.

"I don't think he's in good shape at the moment."

Mana, 35, had also taken to Instagram to express his disappointment in his brother's actions clarifying that it wasn't him and that his twin had "made an extremely bad decision and I am disappointed in his actions".

"While I understand everyone's outrage," he wrote, "please realize I am a twin and this was my twins actions, not mine. I do not find any humour in this, nor would I ever joke about feeding alcohol to a child. I have worked extremely hard to build my own business from the ground up and am so disappointed that someone so close to me could make such poor decision towards a child."

Mana, who is a father of two daughters aged 7 and 9, said he put up the post for people to understand it wasn't him in the video.

"I got nothing to hide, but I put up a post last night just about, not being angry, but I just want people to understand that what happened from that weekend I have suffered from that.

"Firstly, it's mentally and it cost me because it's my business. But my twin, his fight now is for his kids. My fight is for my business ... I'm not throwing my twin under the bus, but I'm like, 'hey that's not me'."

He was unsure if his Australia-based parents were aware of the situation as he was yet to speak to them.

"It's all for social media, you know ... but hopefully he's learnt his lesson."