Mystery 'Sex On Fire' cover version of the day

Name the artist.

Clue One: She's had four Top 20 hits.

Clue Two: She is a she. 

Clue Three: You would probably put her in charge of watering your plants while you were on holiday, but you would not neces­sar­ily leave her with the respons­ib­il­ity of feeding the cat.

Any ideas?