Kate Middleton and Prince William welcomed a baby boy into the world today at St. Mary's Hospital in London at 4:24 p.m., the palace announced, which made the new royal heir a Cancer on the zodiac calendar by a matter of minutes.

"He's literally a hair's breath from Leo, but he's a Cancer," said Susan Miller, astrologer and founder of Astrologyzone.com.

As the word waited today for news of the baby's birth from the palace, there was much online speculation that the royal heir would wind up a Leo, and if the prince arrived nearly a half hour later, after 5 p.m. in London, that may have been the case. His Royal Highness Prince of Cambridge, as he is officially known, will have attributes of both signs.

"Anyone born on a cusp will take the best talents of both signs. He'll take all the sensitivity, caring, and nurturing and shrewd management of money of Cancer, but he also has this other very philanthropic side," Miller said. "And Leo makes him a great ruler."

Cancer, the fourth sun sign of the zodiac, includes those born between June 21 and July 22, notably his dad Prince William, and his grandmother, the late Princess Diana. They're typically sentimental and sensitive souls, and often very nurturing, caring and creative. Those with Cancer birthdays tend to be most comfortable at home, have strong ties to family, and value routine and traditions.

Cancer, also the sign that ran through the Rockefeller family, may mean the baby will be both financially prudent and wise when it comes to decision-making.

"He is going to manage the family's assets in a very responsible way and even make the funds increase in family," Miller said. "Cancers always look for quality and long-term use for whatever they buy and when they invest they think long term."

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Governed by the moon, a female planet, Cancers tend to be more emotional, maternal and nurturing people.

With the full moon today in Aquarius, the sign of humanitarian efforts, the heir is poised to carry out the work of his late grandmother Princess Diana, following her charitable efforts, Miller suggested.

"He will put a refreshed face on the British monarchy and people will love him," Miller said.

The royal baby's rising sign is Scorpio, the same as grandfather Prince Charles, which means the heir will be shrewd when it comes to negotiation and decision-making and that the two will likely share a close bond, Miller said.

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Also at play in the baby's disposition are Middleton's and William's signs - Capricorn and Cancer - which are exact opposites, but complement each other perfectly, astrologically speaking, according to Miller.

"This baby is going to get along so well because the baby's mother is a Capricorn and he's Cancer," Miller said. "Father and mother make a beautiful pairing."

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