She may only be two years old but young Pang Ya already tips the scales at 6.5st(91 pounds) - the same as an average fully grown Chinese woman.
Ya, of Taocun town, Shanxi province, was born at a normal weight of 4kg(8.8 pounds), but has piled on the pounds ever since.
Her worried parents, father Fan Ruixiao and mother Zhang Chunmi, are now desperately looking for a way to help their daughter slim down.
They first became concerned when Ya was just 8 months old and already weighed 20kg (44 pounds).
Scared that something was wrong with their daughter they took her to hospital for a check up.
However, doctors were unable to explain why Ya is the size she is. And a subsequent visit to another hospital in August last year proved to be just as fruitless.
"Doctors can't figure out the reasons for her obesity, which worries us a lot," said Ya's mother Chunmi, who now spends all her time at home taking care of her daughter.
"Doctors have never seen a girl as big as her. We searched the internet and can't find anyone who is heavier than her at her age, so she could be the heaviest kid in China".
Now at the age of two Ya weighs 41.5kg (91 pounds) and has to wear clothes meant for 7-8 year olds.
At just under 39 inches tall, she is almost four times heavier than other children her age and stands out drastically when surrounded by her friends.
According to mother Chunmi bullying so far hasn't been a problem. "No one dares to bully her. She is really fierce".
But Ya's weight is already having serious affects in other areas. "Her weight doesn't stop her from playing but she gets tired if she walks long, and she seldom runs. She also has difficulty in squatting down".
Her parents, who aren't overweight, also admit that their daughter eats a lot compared to other children her age.
An average meal sees the toddler consume steamed buns, noodles and porridge - and she can easily eat more than 1 kilogram of food a day.
"She eats anything that is eatable," comments Chunmi.
"She especially loves sweets, like candies and biscuits. If we don't control her diet she would eat the same amount as us".
Her family has now started to control how much Ya eats, allowing her just two meals a day - breakfast at 8am and lunch at 1pm.
They have also started to give Ya traditional Chinese herbal medicine in the hope that it will help.
"We just want to find a better hospital to find out the reasons for her obesity and have the proper treatment for her, something that will let her loose weight quickly.
"We won't give up. On one hand we'll continue to find ways for her to lose weight and on the other hand we will control what she takes in."
Ya's father Ruixiao adds: "She is too big. She really can't be like this any more"