His pleas to his 69-year-old father to stop ill-treating the family's two dogs went unheeded.
When the son, who is in his 30s, saw a video of his father beating the pets, he decided that enough was enough.
He called the police to report his father for dog abuse.
A neighbour had filmed the elderly man beating the dog and posted it on citizen journalism website Stomp.
In the 19-second clip, he looked as if he was hitting the dog using a dustpan. He also kicked it three times, making the white dog yelp in pain each time.
The neighbour told Stomp that the abuse at Block 651 Woodlands Ring Road had been going on for a while.
He said the man had even used a laundry pole to hit the dogs.
"I was shocked when I saw this. This is not right. He lives with his family, but nobody stops him when he does that to his dogs," the neighbour added.
The son, who declined to be identified, told Chinese evening daily Lianhe Wanbao that he fought with his father over the abuse. He said he had often spoken to his father about his treatment of the dogs, aged two and 11.
"Over the past two years, he often used the cane to hit them. He also wants them to stay in one corner and doesn't allow them to move around," he said.
He was not sure why his father had become irritable in recent years and took his frustrations out on the dogs.
The man complained that his father had tied rubber bands on the older dog's tail, resulting in an infection that needed surgery.
"I kept smelling something rotten at home. Then, when I was bathing the dog, I realised there was a wound on its tail and it was infected."
The son added: "When my aunt came over last Tuesday, she heard the dogs yelping. But my dad denied he abused the dogs.
"He does this when I'm not at home. My mum can't do much although she's at home."
Neighbours told The New Paper the abuse had gone on for years.
A neighbour in her 40s, who declined to be named, said she has heard the dogs yelping in pain since she moved in about five years ago.
The administrative assistant said in Mandarin: "The abuse happens very frequently, at least twice every day."
Though she's not a dog-lover, she said their cries break her heart.
She said: "He hits the dog until it cried. It is really pitiful but there's nothing we can do."
The neighbour suspects the elderly man could be hitting the dogs because they are not toilet-trained.
"Sometimes, when we are hanging out the laundry, we can smell urine from our kitchen. The man also leaves the lower kitchen window open, maybe for ventilation," she said.
She had considered reporting the abuse to the authorities but decided against it.
"We don't want to sour neighbourly ties, especially since we live so near to each other," she said.
Another neighbour said that she could even hear the sound of the whacking from her flat although she lives on a different floor.
The housewife, who wanted to be known only as Madam Ong, 61, said in Mandarin: "It was so loud, I could hear the 'puk, puk' sound. He must have hit it really hard.
"Why do they keep the dogs and yet abuse them? I feel very sad when I hear the beatings. It is heartless. He keeps hitting and hitting," she added.
Sometimes, the man could be heard hitting a dog for about five minutes, walk back into the flat then return and hit it again, Madam Ong said.
Like the other neighbour, she wanted to make a police report but didn't have the courage to do so.
The dogs are in a high-risk situation
The dog in the picture doesn't just look abused, but also neglected, said Action for Singapore Dogs president Ricky Yeo.
"You can't leave the dog confined near the window as it can get heatstroke," he said.
He added that it amounted to abuse since the dog is "constrained and defenceless".
"If this treatment continues, it can become aggressive. If the dog is mild, it will tolerate the beatings. If it is aggressive, it may one day bite the owner," he added.
The dogs are also in a high-risk situation, Mr Yeo said.
"In a worst-case scenario, the father may pick up a dog in a fit of rage and throw it down. It has happened before."
It was good that the son had gone to the authorities, though Mr Yeo thinks the father would be let off with just a warning.
Nevertheless, the son's role has been crucial in ensuring the abuse stops. He suggested the son keep the dogs away from his father when he's not at home.
The son could also get a professional dog trainer to explain to the father how to control the dogs without abusing them, Mr Yeo said.
This article was first published on July 29, 2014.
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