Amy Fitzpatrick was 15 when she suddenly disappeared on New Year’s Day in 2008 from her home in Spain.
Originally from Dublin, she had been living in Mijas Costa, near Fuengirola, in Spain with her mum Audrey, stepdad Dave Mahon and her brother Dean, who has since died.
She spent New Year’s Eve in 2007 with her friends, Ashley and Debbie Rose, near her Spanish home and left the home at around 10 pm to walk a few minutes back to her home but never returned.
Amy was not officially reported missing until January 3 and authorities have struggled to find any leads on her whereabouts at all, but this week a skull, bones and a suitcase were found close to where the teenager went missing without a trace.
The discovery has led to renewed hope her family might finally have answers to a mystery which has dominated their thoughts for more than 15 years.
Here are five unanswered questions in the search for Amy.
What happened to Amy?
Police have never been able to answer any of the simple questions relating to what happened to Amy in 2008.
Her sudden disappearance is one of the most baffling missing persons cases in Irish history.
Her mother marked the 15th anniversary of her daughter’s disappearance earlier this year, but she says she can’t bring herself to acknowledge it.
Tragically, she has admitted she believes her daughter is dead.
Are the remains found hers?
First and foremost the family will be demanding to know the age of the bones.
Amy's aunt Christine Kenny told reporters investigators believe the body "has been there for over a decade", which would put them in the timeframe of the Irish teen's disappearance.
The skull and bones were found in a suitcase in the hills of Mijas, which was where Amy lived with her family.
Why was her phone found at her apartment?
Ashley and Debbie said at the time that Amy always carried her phone with her and even had it on the night of her disappearance.
But her device was found during a search of the apartment she shared with her mum and stepdad.
It has never been established how the phone got back to the property if Amy was abducted on her way home that night.
Was she involved with a drugs gang?
In an interview with the Irish Mirror last year, Amy’s mother said she had recently been told Amy was allegedly being paid by drug lords to sit in the front of their car while they went on "drug runs."
She said: “I didn’t know anything about this. I was told she would sit in the front of the car like somebody’s daughter.
“These men were in their 40s or 50s and she sat there and got paid for just being there in the car.”
Audrey said that she remembers her daughter often going off for periods of time but she believed it was to go to the shops or to hang out with pals.
Who is the mysterious woman helping in the search?
Amy's Auntie Christine recently revealed an anonymous woman who sent her new important information could prove to be vital in solving the case.
Who she is remains a mystery although she insists the people involved in Amy’s disappearance were “well known” to her.
Christine said of her: “This lady has never been given her name, but she has been giving information over the years.
"This information has eventually found its way to me through sources. I haven’t got around to all the bits and pieces. There are about 21 pages in it and it’s ongoing."
