A TOT who has undergone two rounds of open heart surgery has just celebrated his third birthday.

Little Sebastian Martin was just five months old when he had his first operation – and his parents said they were terrified.

Doctors had discovered their son had a hole in his heart.

His father John, 40, said: “Sebastian was struggling to feed or put on weight.

“He became very ill and, after he passed out at home, he was rushed to our local hospital by ambulance.

“He spent his first Christmas there which was an extremely scary time for all the family and a lot for us to take in.

“So much goes through your head. We were very concerned about what our son was having to go through but we also had our then two-year-old daughter to think of.

“We struggled to explain to her what was happening and tried to make sure Christmas was still fun for her.”

The hole in Sebastian’s heart was repaired successfully but months later, John and his wife Julie noticed he was often becoming very short of breath.

Hospital tests revealed he needed a second round of open heart surgery.

At just 22 months old, Sebastian underwent the procedure to cut away scar tissue from the previous operation.

John said: “Scar tissue had begun to form around the patch in his heart, which was causing a narrowing of the artery, so the blood couldn’t pump out of the heart quickly enough.

“Even though we’d been in the position before and we had confidence that the surgery would be a success, the fear we had the first time around didn’t really go away.”

Yet Sebastian made a miraculously quick recovery from the operation.

John said: “Less than 24 hours after the surgery, Sebastian was running around the play room on the ward like nothing had even happened. His recovery has been astounding.”

Sebastian had his first open heart surgery in December 2016 and recently celebrated his third birthday with his parents and five-year-old sister Grace at their home in Polegate.

John said: “He’s just like any other little boy. You wouldn’t know that he’d been through such huge surgeries at such a young age.”

The supermarket manager decided he wanted to do something to thank the cardiology team who saved his son’s life at Evelina London Children’s Hospital in London.

So he decided to take on Guy’s Urban Challenge, a triathlon with a twist which sees racers take on a gruelling 2.5km run, a 15km spin on a static Wattbike, and climbing the 628 steps of Europe’s tallest hospital building, Guy’s Hospital tower near London Bridge.

He took part in the event last weekend as part of the Cardiology Kids campaign, a patient-led initiative which aims to raise £150,000 for the Evelina London cardiology department, and has so far raised nearly £500.

John said: “I thoroughly enjoyed it and it was suitably challenging. I had my family next to me cheering me on, which really helped me push through to the finish as I started to tire. The sense of achievement at the finish is great, knowing I’d given it my all to do my sponsors and the charity proud.”