Our twin baby joy!

It’s double the cause to celebrate for the Duke and Duchess of Cambridge.

Prince William dashed off for a weekend of hunting with his friends, content that his wife – who was keeping their very special secret – was safe in the care of her mother Carole. But when he returned to the Middleton family’s country estate, relaxed and refreshed from his mini-break, his heart dropped. Kate, 30, was white as a sheet, shaking and couldn’t keep food or water down.

Desperately worried Wills quickly phoned her doctor, who advised she come to hospital immediately. It was time for their secret – kept for eight exciting weeks – to come out. The Duke and Duchess of Cambridge are having a baby! While Kate was undoubtedly in great distress, suffering from acute morning sickness known as hyperemesis gravidarum, those in the know say her debilitating condition hints at not only one royal newborn, but two.

Speculation is rife in the UK that Kate could be expecting twins – and Australian medical experts agree it’s highly possible. “The cause of the condition is linked to the raised pregnancy hormone HCG – which often spikes with twins or multiple births,” explains Brisbane-based gynaecologist Dr Gino Pecoraro.

Under the headline, “Could it be twins for Kate?” in respected London newspaper The Daily Telegraph, Dr Tim Draycott said, “Women who are diagnosed with [the condition] are two to three times more likely to be expecting twins than the background rate of one per cent.”