Deirdre Jacob went missing more than 20 years ago, today her father is hopeful that the passage of time will allow those with information about her disappearance to come forward.
Deirdre was 18 years old when she disappeared from Newbridge in 1998.
Last year, Gardaí reclassified the investigation into her disappearance as a murder case.
Speaking to Ray D'Arcy on RTÉ Radio 1 this afternoon, Deirdre's father, Michael Jacob, said that the family remain hopeful that there is at least one person out there who has information about her disappearance.
"These people are 20 years older and maybe much more mature and can look at things in a different light," he said.
The last sighting of Deirdre was by a motorist and his daughter who were driving by the Jacob home at around 3pm on Friday, 28 July 1998.
As the car drove by the house at Roseberry, Newbridge, the young girl in the car noticed Deirdre just inside the gate.
Deirdre had been in Newbridge town centre where she is seen on CCTV twice.
Gardaí have digitally enhanced the footage and it was aired on RTÉ's Prime Time last week as part of a fresh appeal for information.
Mr Jacob said that there has been a very good reaction since the programme aired with a number of calls made to the incident room in Kildare dealing with the case.
While he said it was difficult to keep telling the story of Deirdre's disappearance over and over, Michael said that the family had made the decision long ago to continue to tell the story at every opportunity in the hope that it will lead to a breakthrough.
"Sometimes it gives you the shivers because there is Deirdre walking up the street as normal," Michael said of watching the CCTV footage.
"We often just remark, Deirdre was a fast walker and you can notice this in the CCTV.
He described it as frightening to see the images of Deirdre walking back towards the house and knowing that just 25 minutes later outside the gate of their home was the last time she was seen.
Mr Jacob talked about the constant reminders and the difficulties of things such as big family events.
"You're reminded quite forcibly at any type of family events and group photographs that have been taken since 1998," he said.
"It gives you a jolt. Why isn't Deirdre in that photograph? She should be there but that's not the case."
Michael and his wife still live in the same house and he said that they are constantly reminded of Deirdre and that when they drive through the gateway they picture it.
"Along the road, it's the same," he said. "You might even spot a girl of similar build and you blink for a second."
In his appeal for information, Mr Jacob said that sometimes lifestyles change and people who have held back information, for whatever reason, may now be in a position to come forward.
"The main thing to do is consider what the right thing to do is. We all probably bottle up things, but in this case the right thing to do is to come forward and give that information to the Gardaí," he said.
He emphasised that seemingly small bits of information could help the investigation as it will help them to build a full picture of what happened that day.
"We are asking people to keep a very open mind on Deirdre's case because the investigation has a number of lines of inquiry and it is important for people to look at it in that way," Mr Jacob said.
Anyone with information on the case is urged to contact the Garda Confidential Line on 1800 666 111 or can reach detectives in Kildare on 045-521222.
Listen to the full interview with Michael Jacob below: