Ariana Grande was discovered singing the 'Titanic' theme on a cruise ship.

The pop star was just seven years old when she unveiled her incredible singing voice on the world by belting out Celine Dion's track 'My Heart Will Go On' which sound-tracked the 1997 romantic movie starring Leonardo Dicaprio and Kate Winslet.

Unbeknown to young Ariana, Miami Sound Machine singer Gloria Estefan watched her perform and called her over to tell her making music was her destiny.

During an appearance on Channel 4 TV show 'Alan Carr: Chatty Man', Ariana said: ''I was on vacation with my family and I was doing karaoke and it was a terrible song choice - we were on a cruise and I decided to sing 'My Heart Will Go On' from 'Titanic'. Really dark choice, but I was only six or seven so I didn't know what I was doing. ''After I was done somebody came up to me and was like, 'Gloria Estefan would like to speak to you.' I was like, 'Are you serious?' And my brother was like, 'Are you f***ing serious?' And we went together to go say hi to her. She was like, 'I just want to let you know that you are so talented and do not ever give up.' It was crazy.''

Ariana, now 22, is gearing up to release her third album 'Dangerous Woman' and has already released the first single from the LP which shares the same name.