"I was lazing around on a sun bed one minute and the next thing I knew I had started giving CPR."

Sarah Hodgson was relaxing with her family on the deck of a luxury cruise liner when she was involved in the dramatic rescue of a six-year-old boy.

The mother-of-three from Harpenden was four days a six-night trip around western Europe when the boy was discovered unconscious in one of the outdoor pools of the 338-metre liner as it passed near Breton, northern France.

The boy was turning blue and working with three other passengers, Sarah started cardio-pulmonary resuscitation (CPR).

The 46-year-old said: "Suddenly there was a big commotion and I saw a man carrying a boy who had turned blue.

"It was instinctive. The boy was clearly not breathing and I started giving chest compressions for what seemed like ages. He had swallowed so much chlorinated water that it was like pushing on a hot water bottle.

"I realised I had gone into autopilot and there was no thinking about what to do - I just had to save the child. Finally I felt his stomach moving and rolled him onto his side so he could vomit, after which he started breathing again."

Sarah's husband, Brian, also helped by pushing sunbeds out of the way to clear a path across the deck for the emergency services.

The ship altered course immediately to intercept a rescue helicopter and the boy was airlifted to hospital in Brest, where he made a full recovery.

Sarah, who lives in Grove Avenue, is in contact with friends of the boy’s family and heard the boy is back at school again since the incident in May.

Following the rescue, Sarah and the three other passengers were thanked by the ship's captain and offered a meal in the restaurant of the ship, which is capable of carrying up to 3,600 passengers.

Sarah, who has had experience as an auxiliary nurse in her local hospital, was reminded how to do CPR by her 12-year-old son Charlie who started earlier this year as a Cadet at the Harpenden unit of the first aid charity, St John Ambulance.

She was talking to him one evening in March about what he was learning at Cadets and he told her about CPR and demonstrated what to do.

Sarah, who is a social worker, added: "Although I was very shaky afterwards, this incident gave me a lot of confidence in my skills and I know that I could do the same again. First aid really does save lives.

"Without Charlie I don’t think I would have had the confidence to give CPR. You never know what will happen. I definitely wouldn’t have thought this would have happened given that we were on a relaxing family holiday during half term. Thank god for Charlie and his time at the Cadets."

Charlie, a Year 8 pupil at Sir John Lawes, said: "Obviously it was distressing to witness to incident, but I am so proud of my mum. She was a hero.

"You never know what is going to happen, which is why skills like CPR are so important."

St John Ambulance has around 38,000 volunteers who are taught live saving first aid skills.