Christie Brinkley is a Sports Illustrated swimsuit edition veteran, but she's also 63. Posing in this year's issue makes her the oldest model to ever be featured in the annual magazine. And even though she's white and thin and traditionally beautiful, this move breaks modeling's age barrier in a big way. It pushes back against society's stereotype that people (especially women) are increasingly irrelevant, undesirable, and invisible as they get older. 

Brinkley was surprised to be asked by SI and says she wants to use this platform as an opportunity to fight ageism. "On a personal level, I thought, if I can pull this off, I think it will help redefine those numbers and remove some of the fear of aging," she told People.

If Ashley Graham's iconic 2016 Sports Illustrated swimsuit cover is any indication, the magazine is getting better about showcasing diversity among its models. Of course, we'll always need more. But this is an essential step in the right direction.

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