The posters advertising Halloween parties at Coastfields Holiday Village, Ingoldmells, bring memories rushing back for Jo Hill and Stephanie Barwell.

The last time they saw Anne Simpson, Jo's mother and Stephanie's grandmother, was 26 September 2004 at her new caravan on the site.

They made plans to come back for a family gathering for a Halloween party.

But the next day Jo, 62, received a phone call telling her that Anne was missing.

Anne, who was from Leicester, has not been seen, nor heard from, since.

It was suggested at the time that she had died by suicide.

However, Jo and her daughter Stephanie, 40, say they believe Anne came to harm in some way, and have not given up hope she might come back.

Lincolnshire Police said it was continuing to investigate Anne's disappearance.

A spokesperson said: "Initially, Anne was treated as a missing person.

"New information came to light and an extensive murder investigation was launched.

"No body was found, no charges were brought."

The spokesperson urged anyone with information to contact the force.

Recalling that last weekend brings back smiles, but also tears, for Jo and Stephanie, who calls Anne "nan".

"She was cool and loved being young. If we ever called her grandma, she'd go mad. She hated it because she said it made her sound old."

The family had visited the caravan for the first time that weekend.

"She was not one for going out shopping on her own normally," says Jo.

"But when she moved here (to Ingoldmells), she loved the market. She was showing us all the clothes she'd bought.

"She was so proud she'd been out shopping."

The next morning, at about 08:00 BST, Anne was reported missing.

Stephanie says she does not believe her nan took her own life, partly because she had been so excited about moving to Ingoldmells and had been making plans for the future, but also because a body has never been found.

"Even if she was suicidal, you can't hide your own body after you've killed yourself," she says.

"I believe there's somebody that knows what happened that night," Stephanie says.

"I think whatever happened, happened. But we should have been able to lay nan to rest.

"You try to live your life. You have to live the best you can, but she's always in my head," Jo says.

Stephanie says: "Because you don't know, you make up all these stories. You look at people and wonder if they know something. Or you think she might be in a hospital somewhere having forgotten everything.

"Has she been kidnapped and she's in someone's cellar?

"The only good thing for me is that we still have hope that we will find nan."

"If we do find out what happened, I don't think it will be in my time," Jo says.

Stephanie becomes upset and wipes away tears as she agrees.

"That's really hard. Anne's children will never know what happened," she says.

"Nobody deserves to be dumped somewhere for 22 years.

"She was just having a nice weekend and looking forward to what was to come."

Jo and Stephanie say they don't feel Lincolnshire Police investigated as fully as they could have when Anne went missing, although acknowledged the force carried out "a massive sea search".

In 2012, a 62-year-old man was arrested in Devon in connection with Anne's disappearance, but no charges were brought.

Separately, police also searched Lakeside Caravan Park at Sutton on Sea after an anonymous tip-off.

The charity Missing People said 3% of missing people remain unfound for more than a month.

Head of helplines and reconnections Paul Joseph says: "It's a really tough thing for families to go through.

"We're used to there being stages you can go through to process and come to terms with something - if someone dies for example.

"But when there's someone missing, you don't have that."

Lincolnshire Police said: "This is a very sad case with no resolution for the family.

"We have reviewed the case in 2024 with no new lines of enquiry being apparent and no new information has come to light to date.

"This case is still open and any new information that would assist us in locating Anne will be acted upon."

"I do believe there's somebody out there who knows exactly what happened that night," Stephanie says.

"We'd be really grateful for any tip off.

"For us, it's bringing her home to rest. Just having an end to nan's story. That's the most important thing to us."

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