Cynthia Nixon is living proof that bad things happen to good actresses. Speaking openly for the first time about her 2006 diagnosis with breast cancer on Good Morning America today, the happily outed actress demonstrated exactly how a public figure maintains grace under fire. And even after telling us how one goes about telling their kids they sorta have to undergo an operation, and how to deal with the public's response to her coming out, one of the most intriguing lessons the Sex And The City star shared had to do with which half of a lesbian couple is called "Mom" and which is called "Mommy." Nixon's life lessons, after the jump.

Since Nixon, mother of two, started her four-year relationship with education activist Christine Marinoni, Nixon's children had to adjust from the standard Mummy and Daddy household to the more modern two-mum arrangement. And as Nixon explains, she most often answers to "Mommy" and the shorter-haired Christine is known as "Mom." But confusion still abounds: "Sometimes my son says 'Mom!' and it's obvious he means both of us." In any case, relationships lasting this long are a rarity in Hollywood, and we're glad Nixon's found a way to make the gossip-attracting union last. While the timing of her announcement is slightly suspect (Nixon was diagnosed in 2006, and SATC: The Movie comes out next month), we're going to give her the benefit of the doubt and applaud her for telling her story at a time when she's guaranteed to get the most press. Manipulative? Who cares. The bigger an audience she has, the better.

• GOOD MORNING AMERICA [ABC]

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