Oh, they're sooooo in love!

The word "thrilled" came to mind the second I saw that photo of Prince William and his fair maiden, Kate Middleton, announcing their engagement. Her wide-eyed look of satisfaction and joy, and his smirk of pride and contentment made their way right into my hopelessly romantic heart. Why not? Here is a couple who, despite a tumultuous turn in the spotlight have taken the leap of faith toward lifelong commitment. What could be the driving forces behind their faith and determination? Is it really true love?

No doubt, there will be eyebrows raising and heads tilting as everyone from gossip-mongers to PhDs weigh in on the possibilities of this famous union lasting more than the customary 15 minutes.

But my take as an astrologer -- and the author of "Lovecasts: The Astrological Guide to Lasting Love" -- will predict what will happen and why this was or wasn't the ideal time for the royal lovebirds to announce their engagement.

Astrology's insight can tell them much about their individual personalities -- and their love. Most important, astrology will help them realize what they have to offer, and to cherish the joy of understanding what they each need. As an astrologer who's focused on the topic of making love last, I have advice to offer Will and Kate, based on instincts and actions that come from the very core of their being, the sun signs under which they were born. All we need to do that -- for them, or you -- is a birthday.

Born on June 21, William is a Cancer, and with her Jan. 9 birthday, Kate is a Capricorn. These two signs are opposite one another on the zodiac wheel, and this is, in fact, just about the perfect position for any relationship. Opposite signs fall in love with one another almost despite themselves, because they give one another the things that they lack within themselves. They finish each other's sentences almost from day one, and if they handle it right, this relationship will have a very high probability of lasting a very long time.

There is a twist to the dynamics between this soon-to-be matching set of royals, though. William's Cancer sun embodies "mother's love," the adoring, cuddling, coddling (and often smothering) kind of affection one usually gets from the soft and gentle person who's always there for us. Kate's Capricorn sun, on the other hand, is the sign of the ultimate achiever, the "tough love father" kind of person who holds up a high standard and sets an example of hard work and achievement the rest of the family will benefit from and hopefully also aspire to.

It's easy to see how these two signs fit together, almost like a natural pairing of "Mom and Dad" ... but in William's and Kate's case, the roles are reversed! Traditional, nurturing and sweet, there's no doubt William is quite the Cancer-type catch. He will dote on Kate's individuality, and respect her opinions to as great a degree as his royal duties permit. His first priority, though, will be family, tradition and country, so it's no surprise to see Kate wearing the same engagement ring William's father presented to Diana when they got engaged.

Kate's Capricorn-like determination to succeed is probably one of the factors that played into her persisting on her path to prestigious matrimony, but it will also prevent her from giving in to each and every whim her gushy husband will have.

Far from having any need to carry on the duties of a traditional wife, Kate is likely to keep working on her many projects, which have ranged from a mail order business much like the lucrative one run by her own father, to a bakery she plans to start with her brother. Kate, too, is family-oriented, and respectful of tradition. She will perform the role of a royal flawlessly, and take her obligations to set a high standard of behavior very seriously.

Although William shows Kate that softness she often needs to work on, she may also want him to be more assertive than he naturally tends to be. Meanwhile, William will need Kate to contain her forceful personality so he can appear to be the "man of the house," for the sake of appearances, at least! Also, Kate will have to be very gentle about criticizing William, while he'll have to can some of his complaining. Kate will show William how to keep "soldiering on," even when he's not entirely comfy and cozy. Meanwhile, while he comes to understand that her apparent emotional distance in public is her way of guarding her private passion for him, William will reveal to Kate what it's like to let down her guard and feel the pure joy of living.

This happiness is sure to come to both of them through the birth of any children they might have. Again, they'll have to understand that they have totally different, but complementary parenting styles. William will be pinching cheeks and cooing over tiny triumphs, while Kate is more likely to sternly inject the children with the wisdom they need to form the stiff upper lip one must maintain to survive, especially as a royal. Both will take great pride in their family, and will strive to create a nearly-perfect environment that will also include plenty of private time for them to enjoy.

After eight years of courtship, this couple has proven they can weather the trashy innuendo and nasty rumors the world tosses their way. Their marriage will probably be as much fun and fairy tale as it is hard work and stamina, but astrology will give them the staying power they'll need to be a perfect example of how lasting love can be achieved.

Increased sensitivity from Kate and a firmer resolve from William will help them fall more easily into those stereotypical male-female roles, but perhaps the fact they're not going to be entirely traditional will be great for the United Kingdom and the world! They very well could show us that as long as couples in love take the time to understand one another and lovingly cater to each other's needs, they can each be themselves and even reverse roles so they can create a lasting, caring relationship.

Judi Vitale is an accomplished astrologer and author of the new book, "Lovecasts: The Astrological Guide to Lasting Love." Her masterful knowledge of astrology allows her to give guidance and wisdom to readers and clients. You can email her here.