Jessie J sings her emotional number 'Who You Are' at The Summertime Ball 2013. This image appears in the gallery:Jessie J At The Summertime Ball 2013 - Pictures 11. Jessie J sings her emotional number 'Who You Are' at The Summertime Ball 2013. Picture: PA Photos 20 images See the full gallery: Jessie J At The Summertime Ball 2013 - Pictures