Chris O'Donnell was born with his Sun in the sign of Cancer, known for its cautious and caring ways. He's built a career on playing nice guys, which he probably is, but his Moon in fiery Aries suggests that he's far from the pushovers he plays onscreen.

Chris O'Donnell is a nice guy -- at least he seems like one in just about every role he plays. From "blind" babysitter to Al Pacino in 'Scent of a Woman' to Batman's helpful sidekick Robin, Chris comes across as someone you'd trust. He was especially sweet and understanding as the former Dr. Finn Dandridge, the patient and devoted veterinarian in 'Grey's Anatomy' who never turned against Meredith Grey no matter how many times she slept with Dr. McDreamy. It's no surprise, then, that Chris was born with the Sun in the cuddly and caring sign of Cancer. This sensitive water sign is protective by nature, an instinctively nurturing motherly type -- although there are, of course, a few macho Cancers out there. In Chris' case, Mars -- the most macho planet -- is also in Cancer, making him seem even more sensitive. But as is usually the case, what we see at first is far from the whole story. For example, Chris was born with the Moon -- Cancer's key or ruling planet -- in the independent sign of Aries. The man may be sweet and cuddly, but it's likely to be on his own terms. Aries Moon individuals can be very kind, but they need their space. While Cancers can sometimes be as suffocating as overprotective mothers, Aries types are not emotionally sticky or sentimental.

Aries and Cancer are at right angles with one another, what astrologers call a square aspect. This is a challenging relationship, because it represents a clash of styles or a conflict of needs. Aries is the forward-pushing pioneer and Cancer is the inward-looking introvert. Still, both begin seasons, making them cardinal signs of initiative and immediacy. This gives Chris great spontaneity and the ability to get to the core of a character very quickly, and connect with audiences quite fast as well. The mix of brash Aries with cautious Cancer shows up again in Chris' chart through Venus, the planet of self-worth, love and the arts. His is in bold and fiery Leo, an excellent placement for a performer. Yet serious and restraining Saturn in Taurus forms a 90-degree square with his Venus that keeps him from acting cocky. While the warmth of Venus in Leo comes through in his smile, the containing influence of Saturn adds modesty to his personality. Leo's need for attention is controlled by Saturn, which makes Chris an ideal actor to play the handsome veterinarian who always came in second to the flashy, and arguably more handsome, surgeon. But one of the gifts of Saturn is that it wears well with age, so in time Chris may stop babysitting the blind guy, playing second fiddle to Batman, or waiting for the woman of his dreams to love him … and finally get the attention he deserves.