By Sanjoy Majumder BBC News, Kanpur

Vijay Kumari was unable to post the necessary bail amount of about £120

In a dusty tenement in a crowded neighbourhood in the Indian city of Kanpur, a young man takes out a bright yellow sari from a shopping bag and presents it to his mother.

“Do you like it?” he asks her. “Yes,” is her reply.

It is an innocuous scene, except that the young man, Kanhaiya, has waited a long time to give his mother a gift.

Nineteen years ago, his mother Vijai Kumari was convicted of murder – wrongfully she claimed.

She was granted bail on appeal but she did not have the 10,000 rupees ($180; £119) she needed to post bail. Her husband abandoned her and no-one else came forward to help her.

“I thought I’d die in prison,” she says. “They told me in there that no one ever gets out.”

She was pregnant when she went to jail. Four months later, Kanhaiya was born.

“I sent him away when he got a bit older. It was hard but I was determined. Prison is no place for a young child,” she says.

So she stayed in prison all these years, lost in the system and forgotten.

All she had to keep her going was a passport-size photograph of her son and his visits to her every three months.

‘Think of her and cry’

Kanhaiya spent most of his childhood growing up at various juvenile homes. And he never forgot his mother.

“I would think of her and cry,” he says, speaking softly and with a lisp.

“She was in prison, all alone. No-one else ever visited her. And my father turned his back on her.”

Kanhaiya's mother Vijai Kumari only had a photo of her son in jail Vijai Kumari only had a small photograph of her son Kanhaiya

As soon as he turned 18, he was trained to work in a garment factory. And he began saving up to get his mother out.

Eventually, he hired a lawyer.

“Someone told me about him. He was surprised to hear about my mother’s case.”

The lawyer took on his case and earlier this month, his mother was freed from prison.

Judges expressed their shock at her situation and the “callous and careless” behaviour of the authorities.

They have now ordered a sweep of all the prisons in the state to see if there are others like Vijai Kumari.

The reality is that hers is not an isolated case.

There are an estimated 300,000 inmates in India‘s prisons, 70% of whom are yet to face trial. And many of them have spent a long time in custody.

It is a reflection of India’s shambolic and sluggish legal system where it can often take years for a case to be heard and a trial to be concluded.

But, for the moment, mother and son are reunited and anxious about their future.

“All I want is for my son to be settled,” Vijai Kumari says, her voice breaking and her eyes moist.

“He’s all I have in this world.”

Kanhaiya and his mother plan to approach his estranged father and fight for their rights, including a share of the family property.

But for now, they are taking in the present and trying to make up for all the time they have lost.