At 2.25pm on Monday April 23, 2012, 96-year-old Nellie Herriott left the BHS store in Brighton’s Churchill Square.

She took the 1a bus to Whitehawk Way, near the junction with Whitehawk Road.

She was never seen again.

Despite two years without knowing what happened to Nellie, her family have vowed never to forget her.

Sussex Police continue to review the case every six months but said the chances of her now being found alive were “incredibly slim”.

Her family are now hoping to have her commemorated on a Brighton and Hove bus.

Speaking ahead of the second anniversary of her disappearance today, her great- nephew George Holland said: “The date is always on my mind, but it is very difficult to commemorate someone if you don’t know if they are still alive.

“It’s very frustrating.

“Auntie Nell was the closest thing I had to a grandmother. We were very close.

“She was the sort of person who could always be relied on to make light of a situation.

“I miss her very much.

“How I feel is very wretched and powerless. It’s the not knowing that’s probably as bad as knowing she’s dead.

“We want to commemorate her on a Brighton bus. The local buses carry the names of local people with connections to the city so we hope Nell can be remembered in that way.”

Detective Inspector Mick Jones said: “It’s been two years since 96-year-old Nellie Herriott was last seen getting off a bus in Whitehawk, Brighton, but sadly there have been no new lines of enquiry and her whereabouts remains a mystery.

“The likelihood of Nellie being found safe and well is incredibly slim due to her age and health and the length of time that she has been missing.

"Sussex Police was overwhelmed by the support and help from the public and media at the time of Nellie’s disappearance. It is very sad that despite all of this and an intensive investigation, Nellie is still missing. Our thoughts are very much with her family and friends who still do not know what has happened to her.

“As with any missing person the case will not be closed down completely – it will continue to be reviewed every six months and any new lines of inquiry that come up in the meantime will be investigated.”

Nellie – a fiercely independent pensioner – lived on her own in Bonchurch Road, Brighton. Her support worker Christine Preece visited her flat on Sunday and left her clean clothes for an appointment.

On Wednesday, April 25, 2012, a neighbour reported her missing, but by then it was feared that she had already been away from her home for several days.

Despite an enormous outpouring of support from the likes of Lord Sugar, Sarah Brown, Angela Griffin and Sue Perkins in the days that followed there was no sign of her.

Possible sightings Dozens of possible sightings of the white-haired, 4ft 9in pensioner, dressed in a mauve coat and black woolly hat, resulted amounted to nothing.

The week after her disappearance Brighton was deluged with heavy rain – leading to fears that frail Nellie was almost certainly dead.

A major police search using dogs, community volunteers and specialist search experts was tasked with scouring Whitehawk, Race Hill and Sheepcote Valley.

The search team were tasked with looking under every bush in case the frail pensioner had curled up in a foetal position to shelter from the cold weather – but the expectation was that she could not possibly have survived more than a couple of nights outdoors.

Detectives even then had grim expectations and searchers were warned that they were looking for a body.

At the height of their investigation more than 100 officers were deployed to search for Nellie.

A suspected sighting of her in London Road, Brighton, a few days after her disappearance proved inconclusive – meaning the last time she is known to have been alive was in CCTV footage filmed of her getting off the bus in Whitehawk.

Nellie, who was born in 1915 to descendants of French Huguenots who came to Brighton to escape persecution, was sent to an orphanage with her sister Edith Mary during the First World War.

She told her family they had suffered from the brutal regime which left her resistant to being institutionalised.

Everyone who knew Nellie talks of her fierce independence – almost certainly a result of her early life in the orphanage.

Her family were aware that in the months leading up to her disappearance, whilst she was never formally diagnosed with dementia, her memory was failing her.

Her niece, Lesley Hogg, who lives in Dorset, was called by the manager of the BHS cafe that she used to visit daily, to say that she had been in seven times one day.

But despite her age and deteriorating health, Nellie still insisted on living alone.

Mrs Hogg told The Argus: “The last time we saw her was Christmas 2008 and she got lost on the train journey on the way to us and we said she mustn’t come any more.

“I never saw her again.

“She wasn’t herself on that last visit. She just sat and stared at the TV.

“She was getting really very frail even then so I don’t think she would have survived very long outside on her own.

“I feel guilty that we couldn’t do more.”

Ms Hogg wrote a poignant letter to The Argus imploring other families to do everything they can for their relatives before it’s too late and if Nellie Herriott’s disappearance can teach us anything it is to look out for those we love.

Mr Holland added: “Auntie Nell will always be remembered as a sunny and extrovert character, who never allowed life to get her down.

“She would gladly talk to anyone, whoever they were, regardless of class, colour or creed. She was a true social democrat in this sense.

“When asked by her sister what she would do with her time when she retired, she declared in her inimitable way ‘I will do what I bloody well like’.

“Nellie was intelligent and amusing company. In all the years of knowing her she never complained, but joked about everything.

“She was a fiercely independent lady, who was never afraid to speak her mind.”

A spokeswoman for Sussex Police said that without any firm evidence, Nellie would not be declared dead and her case would lie open and be reviewed if any new evidence came to light.

She added that Nellie’s family could, if they wished, apply to the Chief Coroner to have her death recognised and an inquest would be held.

Anyone with any information about Nellie’s disappearance should call Sussex Police on 101.