Shauna Byrne (10) sadly passed away on Friday morning after a lengthy battle with cystic fibrosis, with a picture of her Westlife hero next to her hospital bed.
Just two months previously, a million Irish viewers watched her dreams came true when she met her favourite popstar on the Late Late Toy Show.
Celebrity agent Joanne Byrne, who set up the meeting, explained how the chart-topping star was upset when he heard the sad news.
She told the Herald how she was just glad that she was able to set up the meeting for Shauna on Pat Kenny's Christmas show.
"I would get a lot of requests, maybe up to 20 every week, from people looking to meet the guys and we would try to help as many kids as we can," she said.
"I got a letter saying how much she would love to meet Nicky and how she was a massive Westlife fan. So I gave her mum a buzz, who explained how she was going on the Late Late Show.
"It just so happened that Nicky was going to be on the same night and it came together. It was great that he could make her dream come true before she passed away."
The youngster was over the moon after appearing on the show and bravely telling host Pat Kenny of her love for the band.
Shauna, who had been in and out of hospital all of her young life, was speechless when her idol Nicky walked out along with his twins Jay and Rocco.
Just before her TV treat, Shauna had spent the previous two weeks in Tallaght Hospital battling the disease. She had been completely in the dark about Nicky's special visit as the show's producers invited her to come on the show to demonstrate a camcorder to the audience.
Pat quizzed her about Westlife and, after much persuasion, Shauna revealed that Nicky was her favourite member of the band.
The host then told her that a special guest had come along to meet her and out came Nicky with twins Jay and Rocco, with Shauna stunned by the surprise.
At the time, her mum Jackie said: "After the show, we were able to get some pictures of him. His wife Georgina was there and his mother-in-law Miriam Ahern was there. Shauna was just so happy."