In many families, brothers from different mothers (or fathers) never give a second thought to the "half" nature of their relationship.
Not so with Cindy McCain and half-sister Kathleen Hensley Portalski. The pair, daughters of Jim Hensley, founder of the beer company that Cindy oversees, sit on opposite sides of the political fence.
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In an interview with US Weekly, Portalski voiced her support for Barack Obama, saying that she and her half-sister share different political viewpoints. Portalski, whose mother was Hensley's first wife, described Cindy as "standoffish" to the weekly. She also said the potential First Lady had never made efforts to reconcile a relationship, though there was no mention of what the original beef between the two had been.
Cindy referred to herself as an only child in a recent NPR interview, though she has another half-sibling from her mother's first marriage in addition to Portalski.
Half-siblings abound in the '08 election. Obama has seven, according to the Chicago Sun-Times.
Research has shown that half-siblings who share a mother tend to have stronger bonds than those who share a father. One British psychoanalyst explained to the Guardian:
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"In polygamous societies, fathers come and go, and what they call siblings are in reality half-siblings. The only ones that tend to be really intimate are those that share a mother." Anxiety about sharing an inheritance might also play a part.
Political leanings can be a divisive factor in relationships between colleagues, friends, family and certainly lovers. But, like Republican Mary Matalin and husband, Democrat James Carville, and this couple shows us, bipartisan love is possible.