On June 4 in 1984, Misa Morimoto's twin sister Miho Yamamoto left her home in the Japanese central city of Kofu to study at the library.
That evening, the restaurant where she worked part-time called to say she had not shown up.
Three decades on, Miho Yamamoto has not been found.
Ms Morimoto believes her sister was abducted by North Korean agents.
US President Donald Trump and Japan's Prime Minister Shinzo Abe hold a summit meeting at the White House. Source: AP
"I have been looking for my twin sister who went missing 34 years ago, at the age of 20. She is highly suspected to be in North Korea as one of many abductees. I believe that my sister is tenaciously living in North Korea, waiting for help without giving up."
The Japanese government officially lists 17 nationals as having been abducted by North Korea.
After years of denial, in 2002, Pyongyang admitted it had kidnapped 13 Japanese in the 1970s and 80s to train as spies.
Following the admission, five were returned to Japan, while North Korea insisted eight had died and say the remaining four never entered its territory.
Dr Leonid Petrov is a researcher at the Australian National University's College of Asia and the Pacific where he specialises in North Korean politics.
He says following the release, North Korea considered the issue as resolved.
"North Koreans claim that those who were kept in North Korea have already been released and repatriated but allegations are that, by Japan, there are more people in North Korea," he told SBS News.
"It's a controversial topic and has always been used by Japan to pressure North Korea."
Japan suspects hundreds more may have been taken and a protracted and emotional campaign has been waged by politicians and family members to keep the issue in the national consciousness.
The release of three American detainees by North Korea has raised hopes for other abductee families. Source: AAP
US-North Korea summit could mean closure
As an unprecedented summit between the United States and North Korea looms, Ms Morimoto is hopeful of the return of her sister, citing the release last month of three US citizens held by North Korea.
"Recently, three American detainees were freed, and when I saw that I wondered, why can America save them and Japan can't save the abductees?" she asks.
It's long been a key issue for Prime Minister Abe and is one of his government’s top priorities.
Ahead of the historic meeting, he's been pushing for President Trump to make it central to the talks, having raised it with him on several occasions.
Now, just days before the June 12 summit, he's in Washington hoping for assurance that Japan's concerns will be addressed at the upcoming talks, with the issue of the abductees at the top of his list.
"If we are to have the summit meeting, the nuclear, the missile and what is more important, the abduction issue, the solution to all these issues must be sought. And I hope that we will be able to realise it at the summit meeting, which will lead to solution of the problem," he told reporters in Washington.
"But first and foremost we need to seek advancement for the abduction, nuclear and missile programs, Japan and US should closely cooperate with each other so that we will be able to see great success for the historic U.S.-North Korea summit meeting. Japan would like to give our all out effort and support."
Precise details of the agenda for the Trump-Kim sit-down are not yet known, but the US president has been clear on his intention to begin negotiating an end to North Korea's nuclear weapons programme.
President Trump has met the families of abductees several times and vowed to address the issue on a number of occasions.
Following their latest meeting, President Trump has assured Prime Minister Abe it will be on the table.
"On the Prime Minister's behalf that he very much talked about abduction. It was pre-eminent in our conversations. He talked about it long and hard and passionately, and I will follow his wishes and we will be discussing that with North Korea, absolutely, absolutely," he said in the joint press conference with Mr Abe.
It's one on a long list of difficult issues on the agenda for the on-again, off-again meeting.
Some are skeptical about whether Washington will be willing to bring up what many view as an issue limited to Japan.
Shigeo Iizuka heads a group of families of Japanese abducted by North Korea. Source: AAP
The ANU's Dr Petrov says even if President Trump raises Kim Jon-un, he's doubtful it will lead to any concrete solutions.
"It makes sense to bring this topic for discussion but I don't think there is going to be much of a resolution because the North Korea government has claimed the problem has been resolved."
Japan has been included in previous rounds of nuclear talks with the North in 2003, known as the Six-Party Talks and included China, Russia, South Korea, Japan and the US.
Dr Petrov says Japan's persistence on resolving the abductee issue at that time was one of the causes of the collapse in discussions.
He warns if President Trump is too persistent on the issue, he risks the same fate.
"I think it's rather a risky area, I think it's the zone which President Trump should mention but not press too hard otherwise the risk that a future summit is going to collapse in the same way the six-party talks were disrupted, is increased."
