The Duchess of York has defended a family from a rundown council estate who were recently at the centre of a drug-death police investigation, and promised they will be friends for life.

ITV said that next week it will broadcast the programme The Duchess in Hull, which was under threat after police arrested a central participant.

Terri Eccles, 24, who put her family forward for the show, in which the Duchess acts as a lifestyle coach, was questioned by police after an 18-year-old man was found dead at her home. The man had suffered a cardiac arrest after a suspected drug overdose.

The Duchess, who helped the family of Tonia and Mick Sargerson to change their diet while living on a Hull council estate, said: “Terri is a lovely girl. There was a legal problem about showing the film but she was completely cleared of any involvement so we go ahead.” Ms Eccles is the daughter of Tonia Sargerson from a previous marriage.

The Duchess, 48, walked out of a screening of her film after the opening section showed her exhausted and without make-up after a gym session.

During scenes filmed in New York, a troubled Duchess describes herself as “fat, ugly and disgusting” and says: “I find it very difficult dealing with the darkness in the mornings.”

Later, the Duchess said: “I got up because I wanted them to cut the first ten minutes. But the producers said people need to see the 'real you'.”

When the Duchess first met the Sargersons, who live on one of Britain's most poverty-ridden estates and have a history of health problems, it was clear that they had no idea who she was. But the former Weight Watchers spokeswoman found “massive love” with the family. She said: “We are good friends now. I have invited the Sargersons to stay with me. I want their children to meet mine.”

Ministers can expect a call from the Duchess, who is embarking on a Jamie Oliver-style campaign to improve the nation's health.

She said: “Meeting the Sargersons has helped arm me with facts when I meet Ed Balls or Alan Johnson. I want to help families — no matter what their budget — improve their lifestyles. Otherwise the Government will face a £50 billion obesity bill by 2050.”

The Sargersons said that they had lost a stone under the Duchess's healthy living plan. Admitting that her own children faced similar health issues, the Duchess asked the media not to criticise Princess Beatrice, 19, who was recently pictured in a bikini. One commentator criticised her figure.

The Duchess said: “Bea is a healthy size ten. People should focus on the fact that she has battled dyslexia to win a place at university.”

For her next project, the Duchess wants to go to Burma to force the authorities to open the borders for aid for the victims of Cyclone Nargis.

The Duchess in Hull, ITV1, Mon, May 19 & Tues, May 20

INTRODUCING FERGIE

The Sargersons wonder who their famous visitor might be

Mick We’ve got Fern Britton, Nigella Lawson, Ricky Lake, Vanessa Feltz and Kerry Ke Tanawa, whatever her name is . . .

A red-headed woman arrives to blank looks

Duchess Did you think it was Oprah Winfrey? Oh my God. That’s so sad. Do none of you know who it is?

Tonia I’ve seen you but I can’t remember your name

Duchess I married Prince Andrew, right, Diana was my sister-in-law. You’ve heard of the Queen of England have you? The Queen was my mother-in-law

Mick How do you do. Nice to meet you

Mikey, 14 She’s all right but I reckon it’s just a publicity stunt

Source: ITV1 The Duchess in Hull

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