Duchess Catherine, 32, is said to want to have three children with her husband Prince William by the time she is 35.
Catherine already has 14-month-old son Prince George and is currently pregnant with her second child, but friends say she's determined to fall pregnant again shortly after the birth because she's keen to raise three kids.
Duchess Catherine - formerly known as Kate Middleton - has two siblings, sister Pippa and brother James, and wants her children to grow up in a similar family environment to how she did, according to the Daily Telegraph newspaper.
The brunette beauty and husband Prince William, who married in 2011, announced they are expecting their second baby after Catherine pulled out of a visit to Oxford University on Monday (08.09.14) due to severe morning sickness.
Catherine always knew that there was a high chance that she'd battle with morning sickness, known medically as Hyperemesis Gravidarum, if she fell pregnant again as she suffered the same complications with George in 2012.
A source said previously: "This bout of sickness has come on very fast and Kate's gone from feeling great to feeling terribly ill very quickly.
"They had thought that she might be lucky and not suffer it this time, but they knew before they decided to have another baby that it was a possibility.
"Kate's very practical and takes everything in her stride and decided that she'd manage to cope and just get on with it if it happened again."
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