An eight-year-old girl with swine flu who died was a "bright light" who will be missed by pupils and teachers, her school principal has said.
The girl was a pupil at Ceara School in Lurgan, County Armagh; a special school for children with severe learning disabilities.
School principal Dr Peter Cunningham said: "She had a smile that would light up a room, and she was just a delight to have at our school."
He said parents should be vigilant.
"In so far as my knowledge of the vaccine exists, I would urge people to take up the offer, although that depends on individual circumstances," he said.
While the child's family is not originally from Northern Ireland, and English is not their first language, Dr Cunningham said the family would have been made aware of the H1N1 virus and offered the vaccine.
Twenty people from Northern Ireland died in last year's swine flu outbreak, including a number of children with severe learning difficulties.
The child was one of two people diagnosed with the virus in Northern Ireland last week; the other case, involving a man, was not linked.
The Public Health Agency (PHA) is recommending that all special school pupils have the flu vaccine this year, even if they had the swine flu vaccine last year.
A PHA spokesperson said the girl's death was a reminder that flu infection can cause serious complications, especially in those with certain underlying medical conditions.
"Children who attend schools for those with severe learning difficulties should receive flu vaccines this year and we have written to their parents and to all GPs asking for them to be immunised as soon as possible.
"This year's vaccine protects against three strains of flu, including H1N1 flu.
"While there is no evidence at present that flu is circulating widely in the community, it is impossible to predict when it will.
"We would advise all those who are eligible for flu immunisation to make sure they get it as soon as possible."
Symptoms of swine flu in humans appear to be similar to those produced by standard, seasonal flu - fever, cough, sore throat, body aches and chills.
Some people with the virus have also reported nausea and diarrhoea.