Singer Mary Byrne, who appeared on the seventh series of The X Factor with One Direction, said the news of Liam Payne's death was "very sad".
The Ballyfermot woman was a hit with viewers in 2010, the same year and Cher Lloyd appeared on Simon Cowell's popular singing show, with Matt Cardle ultimately taking home the crown.
Byrne said that despite not seeing Payne in a long time that she "still felt that emotion" that she connected with when she and One Direction shared a house during the production of The X Factor.
The singer recalled being with them for "almost a year" through bootcamp, judges houses, living together and then touring.
"I got to know the young lads and they were great, Liam in particular," she said.
"I always felt like I was the mammy of the house, and they used to come to me and they kissed me every single morning," she added.
She recalled Liam telling his father that he was progressing to the next stage of X Factor.
"I remember his father saying on the phone 'oh my god that's brilliant, just hold your head together keep yourself strong'," she said.
She described the death as a "shock".
"Liam always gave me the impression that he was the one that had his head on his shoulders," she said.
"That he was the one that kind of guided the rest of the lads, got them up and motivated them to do the job," she added.
She described Liam as having "an old head on his shoulders", adding "he had a great outlook".
Byrne said when acts in the music industry become that big in such a short time "you need to have people around you who are going to hold you and keep you grounded and your mind straight".
She said young people "come in and they're looking for fame, they're looking for this new life and they don't realise, and I didn't even realise, that it is a hard game".
"To think that this young man now at 31 years of age has gone down a road that's so dark and couldn't come back for some reason, it's heartbreaking," she added.
'He just loved to sing' - tributes paid to Liam Payne
Liam Payne: Teenager thrust into global boyband mania who dealt with early fame