Now home with their new baby at Kensington Palace, Prince William and Kate Middleton have started life as a family of five.
"It completes it," says royal biographer Ingrid Seward PEOPLE this week's cover story. A friend of the couple notices that Kate, 36, "is one of three siblings, and it's a good family size, boy-girl-boy is pretty cool too."
Parenting, adds the friend, "suits them a lot They enjoy it and are very happy. "
To learn more about the new royal family, read the issue of PEOPLE this week Friday Friday
Big brother Prince George, 4, and the big sister princess Charlotte, who turns 3 on May 2, "are so excited," says another friend. "Kate is worried that Charlotte is the youngest to feel the hardest, but she's such a confident little girl and growing up so fast, Kate hopes she'll adapt."
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In Kate's hometown Bucklebury, "everyone here is thrilled," says a local. "It's nice that George and Charlotte have a little brother to play with, and Carole will be absolutely overjoyed."
With the new baby as fifth heir to the throne, "hopefully this little boy can live a little out of the spotlight," says another Bucklebury resident. "We look forward to seeing him at the local park."
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