It’s written in the royal stars!

Princess Kate may be celebrating her 34th birthday on January 9 “privately,” a palace source tells PEOPLE, but Princess Diana‘s go-to astrologer, Penny Thornton, has a few celestial ideas about where the Capricorn’s 34th year will take her and – and she is sharing them exclusively with PEOPLE.

Of course, we don’t need to consult a horoscope to know that Kate has a busy year ahead! She has already seen Prince George off for his first day of preschool, will be planning Princess Charlotte‘s sure-to-be-amazing first birthday party, and has tours to Bhutan and India on the calendar.

But it won’t all be smooth sailing for the royal, Thornton predicts – she says that the stars are indicating 2016 may prove to be a challenging year for Princess Kate, where “joy looks to be balanced with heartache and controversy.”

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Check out the rest of Thornton’s predictions for Kate’s 2016 below, and check her out on Astrolutely.com for more horoscopes.

With only a vague afternoon time of birth to go on, it is difficult for an astrologer to make any absolute statements about Duchess Kate. However, I have always thought there was a Gemini element to her nature and appearance, and in the early afternoon this mercurial sign was rising, providing a perfect mirror image of her husband, William, who has Sagittarius rising.

What we definitely know is that she is a Capricorn with her Moon in Cancer. More important, she was born on a lunar eclipse, which is indicative of a powerful destiny.

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Throughout 2016, the great planets of change and transformation, Pluto and Uranus, will be homing in on her chart – making this a potentially challenging and changeable year. Since the royal couple with their two young children are nicely settled in their Norfolk home, the likelihood of a house move is off the menu, so the instability surrounding Kate s home life may well reflect the arrival of a new baby and the disruption to the domestic schedule. There could many staff changes and renovation and redecoration projects.

This is also a complex year for the Queen and Prince Philip. Her Majesty celebrates her 90th birthday on April 21, and although she would prefer to downplay this great coming of age, Great Britain will be celebrating in style.

However, joy looks to be balanced with heartache and controversy, and maybe this too is why Princess Kate is carrying rather more stress on her delicate shoulders than usual.