Good Girl Twin - My twin brother and I are as different as night and day.

Q. My brother was born a minute later than I by C-section. We have never gotten along and are currently estranged, except when he needs money. We seem to be total opposites in all ways, and I was wondering why. In school he was in special classes, while I was in regular; in work situations, I’ve always been a workaholic, while he is lazy; I’m an optimist, while he’s a pessimist; I travel a lot — he’s been on an airplane only recently. The only way we’re similar is that he is a good artist (draws), and I work in clay. What gives?

— Good Girl Twin

A. The situation you describe demonstrates the complexity of the relationship between astrology, genetics, environmental factors, and free will. All of these play a part in determining how a person ultimately lives his or her life. Let’s look at your virtually identical birth charts.¹

The most prominent planet in these charts, based on angularity,² is Uranus near the IC. How ironic that the planet representing unique individuality is so prominent in the chart of twins, revealing that you and your brother actually prefer to be as different from each other as possible. This is augmented by Venus and Mars flanking Pluto, all in Leo in the 5th house of creativity and self- expression, suggesting that your artistic capabilities and the pride you both take in standing out from the crowd — and from each other.

These placements make me wonder how much you each contribute to the other’s way of being. How much of who you choose to be is a reaction to him? What healthier strategy could you, the self-described workaholic, use to distinguish yourself from your brother? If you slowed down a bit, would your twin brother naturally begin to exert himself more productively?

Birth Chart - Good Girl Twin
Natal Chart - Boy Twin
Source: Hospital Records

The 6th-house conjunction of the Moon, Neptune, and Saturn in Libra may indicate an underlying insecurity which is heightened by the square of those planets to 4th-house Uranus. The conflicting desires to both fit in and stand out take their toll through inner conflict. This insecurity is also suggested by the 6th-house Sun–Mercury conjunction in Virgo, square to Jupiter, which can indicate a strong desire to excel, perhaps excessively, in order to play a meaningful part in the world, or it can be the mark of a person who continually spins his wheels, getting nowhere fast, as in your brother’s case. As you have noticed, identical birth charts do not mean identical people.

Additional factors also play a part. Twin pregnancies often place more stress on the fetuses, as demonstrated by your mother’s C-section. Perhaps this stress affected your brother, as the second-born, differently than you. Next, girl and boy babies are not treated the same,³ and even birth order can be a factor. Studies have shown that children in a family differentiate themselves from one another to create their own unique place within the family system. It is said of the first- and second-born in a family that "you can almost guarantee they’re going to be the opposite."⁴ Also, since you and your brother are different genders, you’re not identical twins, and therefore you are no more related genetically than any other brother and sister would be, with only about 25% of your genes in common,⁵ rather than the 100% genetic match of identical twins.

Beyond all of the above, there’s the question of free will. Why does one person make the most out of what she has, while another just makes do? This is one of the enduring mysteries of life that astrology alone cannot answer.