The Church of England's first female diocesan bishop, the Right Reverend Rachel Treweek, is discussing the problem she has with Queen Elsa and Princess Anna, the female leads from Frozen, the animated Disney film. "Everyone says [the film] is really great because the girls have courage, that they are not just typical princesses because they are brave and strong," she said."But they are still beautiful, slim, petite, thin-waisted, big-eyed princesses. The film is still saying if you are going to be successful, you still have to look a certain way."We start with those messages from a young age. They are not good role models."Treweek is on a crusade.This week, she launched a social media campaign to redefine how young boys and girls view themselves and to challenge negative body image, which is creating a new generation with low self-esteem that could lead to mental-health problems.The campaign, featuring photos of schoolchildren with a specific part of their body that they don't like airbrushed out, comes with its own hashtag, #liedentity - a wordplay to stress the fake and unrealistic representations of young people's bodies.Her initiative follows a Children's Society report earlier this year that found a third of girls are unhappy with their appearance.This month, the Girlguiding movement's Girls' Attitude Survey found that more than a third of girls aged seven to 10 believe they are rated more on looks than ability. It found that, in the past five years, body confidence levels of those aged seven to 21 had plummeted.And all this after last week's news that Cardwell & Simons, a photography firm that works in 700 schools across the UK, had introduced a photoshopping service to airbrush away pupils' imperfections. ..