"It was traumatic being in there but she just kept herself positive by drawing pictures and writing poems on the boxes that she had with her in the lift," she said.
"She knew that at some stage help would come so she just had to keep herself positive by doing things.
"She just kept deep breathing to stop herself from panicking."
After she realised she was stuck Campbell proceeded to push the emergency buzzer in the elevator, but no help came, said Sarah.
A light and a fan were going in the lift as were alarm bells, she said.
"She had a MacGyver moment where she put packing tape in her ears to try and block out the sound."
Sarah said that Campbell heard a car pulling up to the building the next day and began calling for help.
"What she realised was at around 6am people would start coming to use their units so she kept an ear out, periodically shouting from 6am onwards.
"When the ambulance and fire people got there she was pretty distressed because somebody had finally turned up and there was nothing to eat or drink in there."
Campbell's lawyer Keith Young sent a legal letter to lawyers for the storage company and the lift maintenance engineer alleging negligence in August. But the engineer's lawyers deny any negligence and said he was not responsible for installation, workmanship or components. A civil claim has not yet been filed in court.
Months after the incident Campbell is still suffering from the traumatic effects of being stuck in the lift. Now she wants answers she told Fairfax.
"Fourteen hours in a lift is nothing compared to how your brain processes it afterwards. It's taken months for me to get rid of some of that anxiety. I don't want to over-dramatise it, it's not post-traumatic stress disorder. I am a reasonably calm and collected person but I have been seeing a psychologist.
"When you feel you haven't been taken seriously it's a bit frustrating. Every time I go into a building I have to know how I get out.
"The first week they [Guardian] were great. They gave me a fantastic big hamper and a bouquet of flowers. They reimbursed me. I wasn't able to work, I had to take some time off. That was just for the first two weeks.
"It's sort of a bit like pass the buck. Nobody has taken responsibility.
"Everybody is saying they did what they were legally obliged to do but I think it's somebody's responsibility if you get trapped for 14 hours. The lift broke. The alarm broke, which meant the security company weren't notified.
"There might be somebody there at two in the morning, so make sure their well-being is safeguarded. They are very sorry, of course.
"There's just no accountability. It just doesn't seem right. It seems unfair. I'd just like to be taken seriously and have my voice heard and for them to take some action."
Campbell's family had alerted emergency services when she did not arrive home and got the "ball rolling" with police to try and find her.
"Then the storage unit company rang me first thing in the morning and let me know she had been found in the lift."
Sarah said it had been a lesson to the whole family to always take their cellphones with them wherever they go.
Guardian Self Storage general manager Terry King said at the time the company was shocked at Campbell's ordeal, which happened at its branch on the corner of Foundry and Anvil roads in Silverdale.
"For this to happen, it is as shocking for us as it is for her," he said.
"The lift basically just stopped. We own five facilities and four have got lifts in them and what would usually happen is that there is an alarm system and you push a button if the lift stops. It goes through to a security company and the security company come and obviously override the system and get you out.
"In this case for some reason the alarm hasn't gone through to the security company so no one has actually known that [the woman] was in the lift until someone found her."
Sarah said her sister was just happy to have been freed.
"She is very relieved to be out of there that is for sure.
"I think it may be a while before Caroline will go into another elevator."
She said the storage company had told her they would be conducting a full inquiry into what happened.
The sisters have now been given a storage unit on the ground floor so they would not have to use the elevator again.