An impoverished father has revealed that he plans to sell his own kidney to fund life-saving treatment for his three morbidly-obese children. Sisters Yogita Rameshbhai Nandwana, five, and Anisha, three, and their 18-month-old brother Harsh, are among the world's heaviest young children. Weighing 5st 5lbs (34kg), 7st 8lbs (48kg) and 2st 5lbs (15kg) respectively, the food they eat in a week is enough to feed two families in a month. Now their father Rameshbhai Nandwana, 34, of Gurjarat, India, is planning to sell his kidney to earn the money needed to see top specialists. He said: ‘If my kids continue to grow at this rapid rate they will have major health issues. We’re terrified they will die.’ Scroll down for video . Obese: (From left) Yogita, five, Harsh, 18 months, and Anisha, three, weigh 5st 5lbs (34kg), 2st 5lbs (15kg) and 7st 8lbs (48kg) respectively . Yogita and Anisha eat 18 chapatis, 3lbs of rice, two bowls of broth, six packets of crisps, five packs of biscuits, 12 bananas and a litre of milk daily. And their extreme hunger means their mother Pragna Ben, 30, spends most of her day making their meals. She said: ‘My day starts with making 30 chapatis and 1kg vegetable curry in the morning. After that I am again in the kitchen preparing more food. ‘Their hunger never stops. They demand food all the time and cry and scream if they’re not fed. I am always in the kitchen cooking for them.’ The couple have one older daughter, Bhavika, six, who weighs an average 2st 7lbs (16kg), and do not know why their other three children are so big. Mr Nandwana said: ‘When Yogita was born she was extremely weak and weighed just 1.5kg (3.3lbs). We were worried for her health. 'So we fed her a lot during the first year of her life to build her strength but by her first birthday she had bloated to 12kg (1st 12lbs). Family: Rameshbhai Nandwana (left), 34, and Pragna Ben (back right), 30, are the parents of Yogita (front left), Anisha (front right), Harsh (front centre) and six-year-old Bhavika (rear centre), their other daughter - who weighs an average 2st 7lbs. They all live together in Gujarat, India . ‘Our third daughter Anisha also gained weight in similar fashion and by her first birthday she was 15kg. ‘But we only realised they were suffering from a disorder when our son Harsh was born as he too gained weight quickly during his first year. 'We started looking for medical help and consulted many doctors but they would just refer us to bigger hospitals that I couldn’t afford.’ Mr Nandwana earns just Rs 3000 (£35) a month - but usually has sufficient money to buy enough food to fulfil the large appetite of his children. He said: ‘I am a daily wage labour and I usually get paid Rs 100 a day but there are times when there is no work at all. ‘I work in fields, dig wells, and do whatever menial job I can find to earn money. 'And I’m constantly worried about finding the money to feed my continually hungry children.’ Despite his paltry income, Mr Nandwana spends about Rs 10,000 (£110) a month on food for his children and said he 'cannot leave them starving' Diet: Yogita and Anisha eat eight chapatis, 4lbs of rice, three bowls of broth, six packets of crisps, five packs of biscuits and 12 bananas daily . Mother of four: Pragna Ben, 30, tries to lift her five-year-old daughter Yogita . 6am . Five bananas . One litre of milk . Six wheat chapatis . One bowl of vegetable broth . 10am . Five wheat chapatis . One bowl of yoghurt . One bowl of vegetable broth . 12.30pm . Millet chapatti - made of 3.3lbs millet flour . Two bananas . One bowl of vegetables . Four packets of crisps . 3pm . Millet breads . Rice - 3lbs with vegetables . 5pm . 1 litre cold drink (Coca Cola or Pepsi) Six packets of crisps . Five packs of biscuits . Five bananas . 8pm . Six wheat chapatis . One litre of milk . Buttermilk (1.5 litres) Two big bowls of vegetables . He added: ‘If I don’t have the money, I borrow it from my brothers and friends. But I make sure I feed my children when they need.’ The father has spent Rs 50,000 (£540) on seeing doctors and treatment over the last three years – without any improvement in his children’s condition. He said: ‘No one in our family has a giant frame. Only my children are overweight. As parents, it pains us immensely to see them unable to move. ‘They cannot walk; they cannot do anything on their own. Selling my kidney is a desperate measure. But I’m now desperate to get the right help for my children.’ Miss Ben cannot pick up her children so she has to watch them roll around when her husband is at work - or use a trolley to pull them around. She said: ‘They need me to help them bath or when they need the toilet. I’m only 40 kg so it’s impossible for me to pick them up. ‘It’s a struggle when my husband is at work. Hard-working: Anisha hugs her father Rameshbhai, with Harsh. Mr Nandwana spends about Rs 10,000 (£110) a month on food for his children . 'They are usually restricted to the same place for the whole day and because of that, they cannot go to school. 'All they do all day is eat and play and giggle with each other. 'I want my daughters to get an education and play like other kids. I want them to have a life. This is no life.’ Local doctors believe the children are suffering from Prader-Willi syndrome, but do not know how to treat it. The rare genetic condition causes various symptoms including constant hunger, reduced muscle tone, restricted growth and learning difficulties. Dr Akshay Mandavia, a paediatrician at Mandavia Children's Hospital in Gujarat, said: ‘There is an abnormal accumulation of fat in these children. ‘They’re not able to breathe properly, and they wheeze. Their condition could be due to endocrinal disease or Prader-Willi syndrome. ‘But we can only ascertain the right treatment after a proper diagnosis at one of our top hospitals.’ Prader-Willi syndrome (PWS) is a rare genetic condition that causes a wide range of problems. These include: . It is caused by a genetic defect on chromosome number 15, which happens purely by chance, and is usually diagnosed by carrying out genetic tests. Sadly, there is no cure for the condition. Prader-Willi syndrome is a rare genetic condition that causes a wide range of problems such as overeating. Parents of children with the condition usually have to restrict their diet and lock up all food . Instead, a team of healthcare professionals will help teach parents to manage any problems the child has, such as overeating. Children usually want to eat frequently, so it is important that most of the food they eat is low in calories, and that access to sweets and fatty foods is restricted. Getting the child to stick to an eating plan voluntarily is practically impossible, so parents usually need to lock any storage areas that contain foods, such as fridge or cupboards. They should also search the child’s room for hidden foods, forbid them to leave the house unsupervised, or play with other children who are eating food, in case they try to steal it. Any family, friends or teachers should be informed of the need to restrict their diet. The child should also be encouraged to exercise as much as possible. If the child has restricted growth, treatment with an artificial version of the human growth hormone (HGH) is usually recommended, as it can increase their final adult height by around 10.5cm (4.1 inches). Most adults with Prader-Willi syndrome are unable to live fully independent lives, such as having a full-time job and living in their own home. Their behavioural issues and problems with food mean these environments and situations are too demanding. Adults with the syndrome who don't live with their parents will probably require residential care. Source: NHS Choices . For more information, visit the Prader-Willi Association website: http://www.pwsa.co.uk .
Sisters Yogita Rameshbhai Nandwana, five, and Anisha, three, and brother Harsh, 18 months, live in India .
They are among world's heaviest young children - weighing 5st 5lbs, 7st 8lbs and 2st 5lbs respectively .
Food eaten by three siblings - who have sister of average weight - in a week would feed two families in a month .
Father Rameshbhai Nandwana is planning to sell his kidney to earn the money needed to see top specialists .