A dad will conquer his fear of heights by walking on top of the 02 Arena to raise money for the hospital that saved his baby’s life.

Thomas King, aged three months, was born with a rare heart condition called Hypoplastic Right Heart Syndrome, essentially meaning that he has only half a working heart.

Now Ryan King, 29, of Dover, will brave walking on the 52-metre high London arena.

He said on his JustGiving page: “This for me is a massive step and just a small thing to raise money and show my appreciation to such as fantastic team of doctors, nurses cardiologists and other staff.

“Without all of these our son would not be here.

“I want to raise as much as I can so that other families will be able to benefit from the fantastic facilities and support this place offers.”

Mr King is helping the Evelina London Children’s Hospital and its fundraising arm the Evelina Children’s Hospital Charity.

Money raised above target will also go to the group Little Hearts Matter, which is for other babies and children with half-working hearts.

By today (Tuesday) £432.50 was raised - 28% of the £1,500 target figure - according to his JustGiving page.

The date of the walk is to be confirmed.

Thomas’ mum and Ryan’s fianceé, Emma Page, 23, said: “I am really proud of Ryan, he wants to overcome his fear of heights but this is a way of giving something back to the hospital, which has been so amazing.

“Immediately I knew this was the right place to go to for help. The care has been so outstanding, right down to every little detail."

Little Thomas was born last December 21, five weeks premature and weighing a frail 3lb 9oz when the average for a new-born baby is 7lb 7oz.

His HRHS stems from a combination of a hole in the heart, a blocked heart valve and a blocked artery between the heart and lungs.

He spent the first five weeks of his life in intensive care before his first life-saving operation on January 24, the day before he was originally due.

Two weeks after the surgery Thomas was brought home for the first time but was rushed back to hospital after he struggled to breathe.

He has so far only spent three days at home.

Thomas is now at the Evelina in preparation for his second open heart operation in May.

He will get his third surgery between the ages of three and four.

You can donate for Mr King’s venture via the JustGiving web page.