You may have seen the case of Roona Begum, 3, last year. She was suffering from extreme hydrocephalus (water on the brain).
When she was taken to hospital her head had swelled to 37 inches in diameter.
Runa's loving parents Abdul Rahman, 21, and Fatima Khatun, 23, were faced with a huge medical bill.
Her head was reduced to 23 inches, but she was given little chance of survival when doctors discharged her.
However, her head is still so big she can't walk.
Doctors are now considering another operation to further reduce the size of her head. Her parents, having seen her close to death on several occasions, are concerned about the risks and debating whether or not to give consent.