Kate Middleton
Kate Middleton wants to have an 'heir and a spare', a friend claimed (Reuters)

Kate Middleton is planning to have "back-to-back babies" after the birth of her first child, according to sources.

The Duchess of Cambridge was planning to get pregnant again before June next year and was hoping to have three children in total, an unnamed friend claimed Now magazine.

According to the source, Kate wants to have her children close together so all three are a similar age.

She would also not have to spend time working to get her figure back only to get pregnant again, friends alleged.

Kate and Prince William's long-time friend told the magazine: "She's so happy about becoming a mother that she's ready to have back-to-back babies.

"After she got over the terrible morning sickness at the beginning of her pregnancy, Kate found it a breeze and loved carrying William's child.

"Now both Kate and Wills think it'd be fantastic for her to get pregnant again as soon as possible.

"And as far as she's concerned, that means giving herself the rest of 2013 to recover from this birth before trying for another baby in the New Year. The hope is that she falls pregnant by next summer."

According to the friend, Kate wants three children like her parents Carole and Michael - the duchess is the eldest of her siblings, Pippa and James Middleton.

She and Pippa are just 19 months apart and Kate wants her a similar age gap between her first two children.

William is also keen on having more children, the friend said. "Kate and William want to get on with it and have another one as soon as possible.

Kate is believed to be staying at her parent's home in Berkshire with William. Camilla, the Duchess of Cornwall, said she expected the baby by the end of this week.

Although Kate and William have said they do not know the sex of the baby yet, her uncle Gary Goldsmith said he believed it would be a girl.

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