A Sussex mother claims to have found a solution to a dilemma which has baffled and infuriated new parents for centuries - understanding why babies cry.

Jules Rumbold, 39, says a hand-held machine is all she needs to win the crying game and guarantee a good night's sleep.

Instead of guessing if her daughter Daisy needs burping, changing or feeding, Ms Rumbold leaves the prognosis to her new digital unit.

The device, called WhyCry, analyses six-week-old Daisy's cry and explains what is wrong.

Jules said: "Not knowing why your baby is crying can send some parents into a panic.

"Babies can't speak so crying is their only means of communication and until you crack the code it is like listening to a foreign language.

"This machine has been an amazing help for me since Daisy's birth by taking away some of that uncertainty. If I am woken up by crying in the middle of the night, I can see exactly what is wrong so I don't have to run through the list trying to work it out. It is fantastic."

WhyCry has been developed by a Spanish electronics engineer and voice-recognition expert after four years of research.

Ms Rumbold heard about the device on the Richard And Judy Show on Channel 4 in January. Intrigued, she called the programme-makers to get more information but was told the machine had no UK distributor.

While on maternity leave she sent a business plan to the company, which was so impressed it gave her the job.

A digital chip inside the machine is programmed to recognise the pitch and frequency of a child's cry. The unit has five illustrated faces, symbolising possible reasons for the discomfort.

It should be placed a certain distance away from the baby, depending on how much he or she weighs, from where it can pick up any sound.

Within 20 seconds one of the noses on the face, symbolising stress, hunger, boredom, tiredness or annoyance, will light up.

WhyCry has been clinically tested on over 100 babies worldwide and has been deemed 98 per cent effective.

Four mothers in Sussex, including a midwife, are also testing the product.

WhyCry costs £65.99. For more details, call Ms Rumbold's company Blissful Babies on 01903 889520.