Handily, her aunt is a music video director, and Muller used to spend afternoons as a runner for artists like Labrinth, for whom she once made tea in a polystyrene cup.
"It was my claim to fame for a long time,"
she told Golden Plectrum.
She's never confirmed her aunt's identity - but it seems likely to be Sophie Muller, the acclaimed director of videos like No Doubt's Don't Speak, Bjork's Venus As A Boy and Beyoncé's Deja Vu.
Sophie also directed the clip for Mika's Grace Kelly, which brings us to this...
When she was nine years old, Muller starred in the video for Mika's breakout single, dancing around in a lime green ballgown, and lip-syncing Grace Kelly's dialogue from The Country Girl.