In March of this year, Catherine O’Sullivan’s son, Jack, went for a night out in Bristol and never came home.

In the weeks that followed, she left the porch light on, just in case he returned.

Six months on, that light is off, but her days are now driven by an ongoing search for answers, fuelled by the family’s belief that police have not done enough.

“I go out daily. My day is planned around which direction I’m going to look next, until I run out of areas I can feasibly check,” she says.

“We basically climb fences, jump into ditches… it gives me the peace of mind that I know that area’s covered.

“I’m Jack’s mum, and my aim on this earth at the moment is to find Jack.”

Jack was 22 when he went missing in the early hours of Saturday 2 March.

He had been living at home with his parents while studying a law conversion course in Bristol, having graduated from Exeter University.

He had gone out for drinks and then on to a house party with people from his course, which he left shortly before 03:00 GMT.

Catherine has previously described how she messaged him around 01:00 to see if he was alright, as he was out with people he did not know very well, and to see if he wanted a lift home.

He messaged back to say he was fine and was going to get a taxi.

But when she woke up just after 05:00 and realised he was still not home, she “knew something was wrong”.

Since then, Jack’s family have been experiencing what missing persons expert, Charlie Hedges, calls an “ambiguous loss”.

“You cannot understand what’s happened. You can’t bring any sort of closure to it,” he says.

“So you’re left dangling, wondering, and the slightest thing that’s said makes you think, ‘Is that something that we need to respond to? Could that find our son or daughter or a loved one?’.

“Tragic and dreadful as it might be, if you lose someone in a fatal road accident or they die from some other means, at least you know what has happened. Unfortunately, with a missing person case, you don’t have that answer.”

Since Jack went missing, the Facebook group Find Jack has gained more than 57,000 members from all over the world.

It has a constant stream of posts, pleas, and theories about his disappearance.

People have offered the family “really good, common sense-approach ideas” to investigate Jack’s disappearance, his mum says, and whilst the public support has been reassuring, some of messages the family have received have been far from it.

“I have had messages suggesting that Jack is being held and asking for ransom amounts for him,” she says.

“People telling me that awful things have happened to him and where I might find him.

“But what would anybody do in my situation? I have to read them, as bad as I know it is, putting myself through hell at times, but I can’t ignore anything.”

There’s a side to Catherine that is happy that people are taking their search for answers so seriously, but at the same time it hurts her.

“I never thought I’d be seeing Jack on a billboard in [Bristol shopping centre] Cabot Circus,” she says.

For the family, life still feels stuck on 2 March.

Catherine points to potential areas that could have been missed on her large OS map covering the kitchen table.

“We’re no further forward with sightings or anything that would give us an indication of which direction Jack went, or where he is now,” she says.

“We’re down to a once-a-week email contact from police only, but we’re going nowhere. They’re not answering the questions.”

In June, Jack’s parents lodged a formal complaint against Avon and Somerset Police over its handling of his disappearance.

Following the complaint, the police made a voluntary referral to the Independent Office for Police Conduct, who recommended a local investigation be carried out.

The family say mistakes were made early on in the search and that CCTV footage, placing him in a different location at a different time, was initially missed.

It was only found by Catherine when she was allowed to view some of it for herself.

In July Catherine also got permission from owners to search an electricity sub-station on Granby Hill that she says police overlooked, despite it being metres from his last known location on the Find My Friends app.

“We feel very unsupported by the people we think should have done the most,” she says.

Police say the location was considered and found to be inaccessible, and that CCTV was checked and did not show Jack.

“We ask for information from them to help us with our searches, which they can’t provide, because it’s an ongoing police investigation… technical information surrounding his phone that we’re not allowed to see for ourselves – even though the phone is registered to myself.”

The information she refers to is the location of the last signal given off by Jack’s iPhone to the Find My Friends app at 06:44 on the morning he went missing.

The family’s privately hired investigators are ready to help, but the data they need is in the hands of police, Catherine says.

“We’re just asking for it because we have very little faith in the police getting it right.

“A few days ago, I met someone who said, ‘Well I have do have Ring [doorbell] footage. I live in a street off Granby Hill where Jack’s phone lasted pinged and nobody has ever asked to view it’.”

Assistant Chief Constable of Avon and Somerset Police, Joanne Hall, says the law prevents them from sharing the requested information.

After the family got access to limited CCTV from the area where Jack went missing, recorded on that night, they were able to see that many vehicles would have gone past him at that time in the morning.

Police previously said that “about 400 vehicles” would have passed underneath Jack in the time period of the last suspected sightings of him crossing a flyover.

“There are all sorts of lorries, trucks, an ambulance, normal cars… people,” Catherine says, as she insists that somebody out there knows something about where Jack went.

She admits the family “lead a very unusual existence”. An “unimaginable” and “awful” one in fact.

“For me, there’s a huge drive of I must keep going. But some days that’s easier said than done,” Catherine adds.

“Our sole focus on a daily basis is finding Jack. We keep going because we owe it to Jack.”

Avon and Somerset Police say that since Jack’s disappearance, more than 20 different teams and departments have been involved in the investigation.

They have been supported by other agencies and emergency services, such as the fire and ambulance service, National Police Air Service, and RNLI.

In the investigation to date, there have been more than 100 hours of CCTV reviewed, 200 hours of searches on the river and the surrounding banks, mounted police searches from Bristol city centre to Flax Bourton, 40 land searches, and 16 drone deployments.

The force says it has received almost 100 calls from the public with possible sightings, and eight media appeals have been issued.

Assistant Chief Constable Joanne Hall, who met with the family in July to discuss their concerns, said: “Our staff and officers remain committed to doing everything we can to find Jack and we do not underestimate what a distressing time this has been, and continues to be, for his family.

“When I look at missing persons investigations [in Avon and Somerset] over the last year, we’ve had around 5 and a half thousand.

“Missing people are somebody’s loved ones, they’re somebody’s family, and we don’t close the door on that.”

Further searches are planned following information and advice received from other law enforcement agencies.

Police say they will update Jack’s family when their handling of the complaint is finalised, and are once again renewing their appeal for any witnesses from Saturday 2 March to come forward.

For the family now, their initial first day shock has been replaced by something different.

A grim realisation that this isn’t a nightmare they will wake up from, this is just their awful new reality.

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