Mr Cameron's friendship with Rebekah Brooks and other members of the Murdoch inner circle - he was at school with her husband, racehorse trainer Charlie Brooks, and the couple socialise with the Camerons - is well-documented.

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Sure, we care about Jennifer, but we follow her life, and the life of other celebrities, mostly because they are now in our "friendship circle, " however illusory this perception is.

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They were compared with 84 same-sex couples in their friendship circle who didn't get civil unions, and with 55 heterosexual married couples in which one of the spouses was a sibling of one of the same-sex couples in a civil union.

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