Sarah Ferguson said her daughter was fit and healthy
The Duchess of York has accused parts of the media of making "outrageous" claims that her daughter is overweight.
In an interview with the BBC, Sarah Ferguson said her eldest daughter Beatrice was a fit and healthy size 10.
"The press has been absolutely outrageous, calling her such horrible names... I just think they ought to take more responsibility," she said.
Her remarks come ahead of a TV show in which the duchess helps an overweight family to improve their lifestyle.
The duchess is a spokesperson for WeightWatchers and has long been concerned about the issue of obesity.
In recent weeks, some sections of the media have criticised 19-year-old Princess Beatrice's figure after she was photographed wearing a bikini on holiday in the Caribbean.
The most important thing we need to do is get people to understand: walk to work, or walk up stairs, take exercise, drink lots of water
Sarah Ferguson, Duchess of York
"Her comment was 'will they be happy if I get anorexia because then they would write about that?'" Sarah Ferguson told BBC Radio 4's Today programme.
"The thing is she is a regular size 10. She's very fit and well and healthy.
"I understand freedom of the press but what I don't understand is when it takes a regular, very healthy girl and tries to completely obliterate her confidence."
She also spoke about how the family she helped in Hull as part of the two-part reality TV programme for ITV were typical of many others on low incomes.
She said they had not been educated about the ways they could make small, but significant, changes to their lives.
"Dad had diabetes and is now getting over it and I had to say to him 'you do realise, if you go on like this, you could be paralysed, you could lose your limbs', and I think it just gave him such a wake-up call, he'd never been told that," she said.
"The most important thing we need to do is get people to understand: walk to work, or walk up stairs, take exercise, drink lots of water.
"And you know, you can turn on the tap and drink water without having to pay for it."
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