But shockingly rather than seeking a doctor's advice, she immediately cut her daughter's daily calorie intake to between 500 - 750kcal (the recommended daily amount for a 12-year-old is between 1,600 - 2,200 calories).
And Donna also ignored her husband's fears that Danielle, now 13, might develop anorexia, due to Donna's extreme measures.
Danielle, who weighed 9st aged 12 - two and half stone above average for her 5ft frame - lost two stone in six months.
Aspiring model Donna, from Brighton – who is married to Patrick, 35 and has five other children aged between three and 15, who are all healthy weights, says: "Danielle was miserable and I wanted to help.
"I'm a size six and restrict myself to 800 calories a day, so I knew it'd work for Danielle. My husband was worried she might develop anorexia but I knew she wouldn't and thought it was worth the risk.
"People might criticise my method but there's a huge obesity problem with children in the UK and Danielle's proof that if you cut your calories you get results."
Read the rest of this story in Closer mag, out today.
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