As royal couple Kate Middleton and Prince William count down the days until their third child is born in April, the royal couple has enlisted the help of Britain’s hottest — and most adorable! — design experts to help decorate the nursery: Prince George, 4, and Princess Charlotte, 2. “Kate wants them to participate in making the baby feel welcome, so she’s allowing them each to choose a special stuffed animal to place in the baby’s room,” royal expert James McCourt exclusively tells Closer Weekly.

McCourt adds, “Charlotte has even started practicing her big-sister skills on her dolls!” Kate, 36, is thrilled with how well her little ones have embraced the idea of a new sibling, though she can’t believe how fast time is flying. “She admitted only the other day that she still thinks of Charlotte as her baby,” Katie Nicholl, royal watcher and author of [Prince] Harry: Life, Loss, and Love, tells Closer.

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The Duchess’ sentimental mood is only eclipsed by the excitement she shares with everyone in England. “The royal baby is boosting the mood of the whole country,” McCourt insists of the growing frenzy. “The queen can’t stop talking about the arrival of her new great-grandchild, and Buckingham Palace is buzzing,” an insider confirms to Closer. Despite Kate’s struggles with severe morning sickness — which she also endured while carrying her first two children — she’s remained upbeat throughout her third pregnancy and the kids are sharing her enthusiasm.

“George and Charlotte had the news about a new sibling broken to them while having cupcakes after dinner,” McCourt says, and their reactions couldn’t have been better.” George couldn’t stop rubbing his mother’s belly! He was too young to understand when Kate was pregnant with Charlotte, but this time he’s very excited.” Charlotte took the news like a champ as well. “She’s thrilled to be a big sister,” McCourt says, “and she looks out for Prince George, even though she’s the younger sibling.”

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To ease Charlotte into the idea of having another brother or sister, Kate helped foster her sense of independence. “She was keen to get Charlotte settled into nursery school well before the third baby comes along,” Nicholl explains. “George is very happy at school and Charlotte has settled in well, too, I hear.” At home, the royal couple isn’t expecting any trouble once the baby comes. “Kate’s a stickler for routine. As a result, the children are impeccably behaved,” Nicholl says. “They have a nanny but they’re still encouraged to tidy up the playroom. Kate always insists they eat their veggies, too, and table manners were drilled into them from an early start.”

That stems from Will and Kate’s shared desire to not allow their socially and financially privileged kids to become “spoiled brats,” the insider explains. “They have set rules for the children and use ‘time-out’ techniques if they ever fight or throw food. And they don’t allow them to stay up late.” Their good behavior is rewarded with plenty of fun, though, which the new baby will soon be joining in on, too.

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“Charlotte’s obsessed with anything Disney and loves dressing up in her princess costumes and singing along to nursery rhymes,” the insider says. “William and Kate joke they’ve got a little actress on their hands!” She’s also good at sports and “is showing more aptitude” at soccer than George, McCourt adds. “George is getting into the game slowly, as he’s more keen on his scooter, which he races around on in the Kensington Palace grounds.”

A onetime Peppa Pig fanatic, the young prince’s maturing tastes finds him more into Fireman Sam these days “and he insists William is really into it, too. He’ll get very upset if his father doesn’t show due diligence to the characters!” As dad William, 35, has said, George is “a bit of a rascal!” Kate, who has an art history degree, “spends time doing crafts with the children,” McCourt says, “and she regularly takes them to the Natural History Museum. She’s even tried teaching George how to cook by making chocolate crispy cakes, but she said the chocolate and golden syrup went everywhere. It was chaos!”

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Still, the royal couple love these precious memories with George and Charlotte, and they pride themselves on being active and present parents. “They’re both noticeably hands-on,” McCourt assures, adding that the couple have said they don’t want to hire any additional nannies beyond George and Charlotte’s current one, Maria Turin Borrallo.”With the kids in school during the day, they feel they’ll be able to cope,” the insider says.

Besides, “Kate will obviously be at home more looking after the newborn during those early weeks,” Nicholl explains. “I expect we’ll see William doing the lion’s share of the school drop-offs, which he really enjoys. According to one of the mothers at George’s school, he’s very chatty and approachable!” Kate’s secret weapon after the baby comes will be her mother, Carole Middleton. “There’s every reason to believe Grandma will be on hand this third time around,” McCourt says, pointing out that Carole was Kate’s go-to helper after her previous two births.

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Kate and her mother Carole.

Despite some talk that Kate planned to have this third royal baby at home at Kensington Palace, royal insiders say she’ll return to St. Mary’s Hospital in Paddington, London, where Princess Diana gave birth to both William and Prince Harry, and Kate delivered both George and Charlotte. “Kate’s first two children were both born in the Lindo Wing,” McCourt says, and Kate has reportedly booked one of the ultra-exclusive suites there for the big day.

In addition to the hospital’s state-of-the-art equipment and supervised nursery, Kate’s suite will provide her with high-speed internet service, a safe, a fridge, and a television. Alan Farthing, Kate’s obstetrician who along with a team of doctors delivered George and Charlotte, “was supposed to file for retirement last year,” McCourt adds, “but the
54-year-old decided to postpone it so he could be there for Kate’s third child.” Once the baby comes home, he or she is sure to be equally as comfortable in the nursery that Kate has personally designed.

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Kensington Palace.

“She chose gorgeously serene floral wallpaper that was custom-made,” McCourt reveals, “and there will be lots of white, soft pinks, and greens, I’m told.” Known for her thriftiness, Kate opted not to splurge on many new furnishings. “The nursery will be filled with hand-me-downs, including George and Charlotte’s old toys,” McCourt adds. Kensington Palace no doubt will be bustling with activity as William and Kate settle into their new routine. “It won’t be easy for them with three children vying for their attention,” Nicholl says, “but they are a very solid and happy couple, so they’ll make it work!”

The young couple is expected to pencil in some private, adult time to help keep their romance alive. “They’re planning on having date nights once a week,” the insider reveals, “and they’ll continue going on double dates with Prince Harry and Meghan Markle.” William’s brother, 33, and his fiancée, 36, will tie the knot just weeks after Kate’s due date, so this spring is shaping up to be an eventful one for the royals. “Harry and Meghan can’t wait for Will and Kate’s baby to be born,” the insider says.

“They’ve spent hours shopping for cute baby gifts and Harry’s been a fantastic uncle to George and Charlotte.” Plus, the insider adds with a wink, “Harry adores children,” so don’t be surprised if there’s another royal baby announcement in the near future.

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