Producers spent three months filming staff and children in a childcare centre to create the Bank Holiday special, Creche Landing.

The idea came from writer David McGrath, one of the team behind the Safeway supermarket chain's Molly and Harry ads, in which youngsters express their thoughts in adult voices.

He said: "It's all based on the babies completely misunderstanding what is going on.

Sir Donald Sinden: Voices tubby Conrad

"One of the carers was pregnant so we came up with the idea of one of the babies disappearing and the others seeing her stomach, thinking she had eaten him and wondering how to get him out of there."

McGrath said the babies were chosen before they came up with the celebrity voice-overs.

"One of the babies, Conrad, was a tubby little chap so we thought we'd make him talk about food all the time with a plummy voice and we eventually came up with Donald Sinden.

"We had to make sure they were recognisable voices that would match their personalities but were also very different so there was no confusion for viewers."

Bob Mortimer: His toddler narrates the programme

Mel G - who herself has a six-month-old baby, Phoenix Chi - provides the voice of a toddler who ends up fighting with Lily Savage's child, "a belligerent little thing" called Freya.

McGrath adds: "We thought she would suit Lily Savage's voice. We were worried her mum might be furious, but she just said, 'Oh, I thought you'd come up with someone like that'.

"Bob Mortimer voices the baby that narrates the show, who had to look into a camera. To make sure he looked at the camera, we had to show footage on the autocue, but when we showed him film of his mum he burst into tears, We ended up showing him the Teletubbies."

The show is produced by Tiger Aspect, the company behind Mr Bean on ITV, Harry Enfield's BBC series and Channel 4's Stella Street. McGrath hopes ITV will commission a full series of Creche Landing if Monday's programme is a success.