The family of a one-year-old Dublin boy, who was born with an incomplete oesophagus, is flying to the US next week for emergency treatment.
Sergio O'Connor, a twin, was born on 5 March 2011 with a number of complications.
Among the severest is a rare condition called tracheoesophageal fistula with long gap atresia, which prevents him from eating, drinking or swallowing.
On Monday, Sergio and his parents, Donal and Rosa, will leave Casement Aerodrome, Baldonnel, to begin his life-saving treatment at the Boston Children's Hospital.
The operation will involve inducing the boy into a coma for approximately three to six weeks, while surgeons use a procedure to stimulate the growth of his oesophagus.
His father will remain in Boston for the duration of the treatment and aftercare, while his mother will eventually return to Dublin to look after Sergio's twin brother, Tadhg.
The family needs to raise €100,000 towards the cost of the operation, which is being supported by the Health Service Executive and the VHI.
The family also has to fund all expenses for the duration of Sergio's stay in Boston, which is expected to take several months.
They have set up a website, helpsergio.com.
Meanwhile, another Dublin toddler who suffers from the same condition is due to be flown home from Boston by the same Air Corps team on Tuesday.
After several operations Elie Madden, who is also a twin, has recently taken her first meal and has been able to use her voice for the first time.
Her website is eliemadden.com.