What a difference a day makes. Months ago, when it was revealed that Kate Middleton's due date was in mid-July, many people speculated that the royal baby would be born under the zodiac sign of Cancer. And if the Duchess had given birth early enough on Monday, July 22, those people would have been right. But as there's still no news that the royal baby has made an appearance, he or she is likely to be a Leo, astrologers say.

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The two signs are right next to each other on the zodiac calendar, but they couldn't be less alike. Cancer is a water sign; Leo is a fire sign. Cancers are ruled by the moon; Leos are ruled by the sun.

There are personality differences, too. To begin with, people born under Cancer, according to Astrology.com, are "all about home." They tend to be nurturing and domestic, and they take great pleasure in family and community. Leos, on the other hand, take pride in being the center of attention and the "king of the jungle" -- hence the Lion symbol.

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Cancers also tend to be quite sensitive and moody. They've been known to brood and retreat into themselves emotionally, and they often avoid confrontation. Leos, meanwhile, are outgoing and bold and rarely shy away from anything or anyone.

Selena Gomez, Jaden Smith, Tom Cruise, and Khloe Kardashian are among some of the many celeb Cancers. Famous Leos include Barack Obama, Demi Lovato, Jennifer Lopez, and Madonna.

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In any case, astrologer Patrick Arundell says the royal baby will likely exhibit personality traits from both signs. "Either way, he or she is going to be larger than life, charismatic and glamorous, but they will have a very Cancerian personality, whether under the sign of Leo or not, and be sensitive and caring," Arundell told the U.K.'s Telegraph on Monday. "If the baby's born today, it will have a slightly more conventional and conservative personality, but if it's born tomorrow it will be more groundbreaking and more in tune with modernity."

This article originally appeared on Usmagazine.com: Kate Middleton in Labor: Will the Royal Baby Be a Cancer or a Leo?