Sinead O'Connor, who died today aged 56, attended Newtown Secondary School in Waterford during the 1980s.
One of her teachers during that time was Joe Falvey, who she often credited with encouraging her to pursue her musical ambitions.
"In the mid 1980s she was in Newtown for fifth and most of sixth year," Joe told WLR News.
"She was due to sit her Leaving Cert in 1985 but music became a major force in her life during the course of sixth year and she actually didn't stay to do the Leaving Cert."
Joe said he had observed and heard Sinead singing around the school in "an informal way".
"When I was listening to her, I said 'I don't recognise any of those songs, who are they by?' and she said 'I wrote them myself'. On another occasion, she said she wanted to enter a song into a song competition so I arranged for her to do a recording with a friend of mine who had a studio in Fermoy."
Joe explains that initial public performances took place at T and H Doolan's in Waterford City.
"I asked the lads there to give her a slot when she was still about 16/17. That was the first time I saw her perform in front of an audience and it was obvious that she had an amazing talent. I said 'wow, she is something special'."
Joe says he attempted to persuade Sinead to remain at Newtown to sit her Leaving Cert exams but she decided to leave and pursue her dream.
"She kept in touch and then I heard she had gone to England," he explains. "One day there was a postal delivery and it was a copy of her first album, 'The Lion and the Cobra'. That was the beginning of her international career."
Sinead's most successful year was 1990 with the worldwide hit 'Nothing Compares 2 U' which Joe says displayed her "raw honesty".
"That song created a major audience for her which endured," he says. "Even her critics couldn't deny her talent."
Joe has often been credited by Sinead as having encouraged her in her music career.
He adds: "I was pleased to get her recognition over the years."
This evening, Sinead O'Connor's family issued a statement saying "It is with great sadness that we announce the passing of our beloved Sinead, her family and friends are devestated and have requested privacy at this very difficult time".
The cause of the singer-songwriter's death is not yet known.
