Just months ago the 19-year-old, known by the stage name Tones and I, was living in a van and singing on the street in the coastal town of Byron Bay, south of Brisbane.

Now her latest release has reached number one in 18 countries including Britain, France and Germany, as well as at home where it broke the record held by Ed Sheeran’s 2017 smash “Shape of You”, which spent 15 weeks at the top spot.

Before her debut single “Johnny Run Away” came out in March, Watson had spent a year playing her keyboard in public, too nervous to speak to passersby between songs.

But while she is now selling out shows worldwide, the singer says she looks back on those days with fondness.

“When I was busking, when I was paying for petrol with silver coins or when I was sneaking into hostels so I could park my van up and sleep in it, I had the best time of my life,” she told Nova radio.