Mark Warner resorts attract families with young children because of the company’s range of childcare facilities.

Ocean Club at Praia da Luz boasts six childcare clubs, catering for children from four months to 13 years old.

The baby club, for those aged from four to 11 months, has one nanny for every two babies and costs £260 a week extra. Qualified nannies also care for the younger children in creches.

One former Mark Warner nanny, Jo Cook, from Melton Mowbray, said: “We would work six days a week, starting at half-eight and finishing at six”. Now 27, Mrs Cook joined the company at 19 and worked seasons in Greece, Turkey, Switzerland and France.

Twice a week they would work later, until 7.30, supervising children at “high tea”, and twice a week they would be on evening duty, supervising a creche or on the “room listening” service that is provided in some resorts.

Parents arriving for dinner gave their children’s names, their room number, and their table number in the restaurant. A group of nannies would circulate, listening at each child’s bedroom.

At the sound of crying, a child’s distress would be reported to parents. This service was not provided at Mark Warner’s resort in the Algarve, however.

Mrs Cook told The Times: “A lot of the nannies were excellent, but occasionally I would see one fall asleep while supervising children, and I have seen a nanny lose a child.

“We nannies were all there earning a pittance — £75 a week for those on their first season — trying to travel the world without having to pay for it.

“It felt very safe, but if someone is really out to break into the resort it’s quite a frightening prospect.”

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