A four-year-old boy has to drink more than 20 litres of water every day because he has an unquenchable thirst caused by a rare kidney disorder.
Dominic Webster suffers from nephrogenic diabetes insipidus, a condition that affects just one in 25,000 people.
The rare disorder means his body's water regulating system is disrupted, causing him to suffer from extreme thirst.
Not only does Dominic drink gallons of water each day, he must also maintain a low salt diet and could need a kidney transplant when he is older.
Mum-of-four Katie, 28, of Horwich, Greater Manchester, suspected something was wrong when Dominic was born and a scan eventually confirmed her fears.
She told her local paper: "I felt sad that he will be able to lead a normal but very limited life. "He's very clever and will say to people he has a kidney problem.
"He has to have a diet low in salt, sugar and protein with few processed meats. He drinks up to 20 litres a day.
"When everybody at nursery is having cake and fruit drinks he can't have them."
But Dominic can eat most of the same meals as his siblings – Jordan, 11, Abigail, 10 and five-year-old Isabel – as his mum cooks his food in a different pan and without salt.
Dominic is not on any medication but has undergone several operations while under the care of three specialists at Royal Manchester Children's Hospital, and he has appointments every six weeks.