What Keeps Heidi Klum and Seal So in Love?

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Heidi Klum turns 38 today -- and life is good. Married to musician Seal since 2005, supermodel Klum and her pop-singer hubby have one of the strongest, most envied relationships in Hollywood. Both are extremely vocal about their love for one another, even renewing their vows twice while raising their four children. So, what is the magic that keeps them together?

Oddly enough, their charts are not obviously compatible: Heidi is a Gemini, and Seal a Pisces -- and their strongest astrological point is her Mars, the passion planet, in Pisces. However, being that most of Klum's planets are in Gemini (Sun, Moon, Mercury, Venus and Saturn), she is constantly changing, as her sign is one of duality. One of the only other signs of the zodiac to also have duality is Pisces. Because of that, their relationship is always expanding and spontaneous; Klum and Seal approach life and love in the same way and always keep each other curious. For Heidi and Seal, following their imagination is what keeps their magic alive!