All parents-to-be nickname their unborn babies, and it seems the Duke and Duchess of Cambridge are no different.

Kate and William have given their baby, due in July, the moniker 'Our Little Grape' - a fetus being the size of a grape at nine weeks - according to US Weekly.

And with only a few months to go until HRH The Baby of Cambridge makes his or her appearance in July, mother-to-be Kate is making sure she stays fit and healthy right up until the birth.

The Duchess of Cambridge is well-known for a love of rigorous exercise, but has reportedly swapped her high-impact running habit with gentler power walks, taken several times a week accompanied her black Cocker spaniel Lupo, 'just to increase her heart rate a little'.

Kate has also employed an instructor to give her private prenatal yoga classes at Kensington Palace, a source told the magazine.

And Prince William's wife is said to be giving in to her sweet-toothed cravings. The insider said 'She's got sugar on the brain. Chocolates, biscuits, cake. When she sneaks off to a nearby Starbucks for a decaf coffee, she'll often pick up a baked good!