Happy birthday today to Calista Flockhart. At 51, not only is the actress incredibly fit and fabulous, but her career is still thriving.

Just this year, Flockhart took on a whole new acting gig when she was cast in the recently released CBS TV series, Supergirl, which is based on the DC Comics character Supergirl. In her new role, Flockhart plays Cat Grant, the fiesty founder of media conglomerate "CatCo" and boss to Kara Zor-El (aka Supergirl).

Before landing her latest acting venture, Flockhart has long been considered a Hollywood A-lister. Emerging on the acting scene in 1997, Flockhart landed the starring role in the Fox TV series, Ally McBeal, for which she won a Golden Globe in 1998. Later, in 2006, Flockhart began work on the ABC critically acclaimed show, Brothers & Sisters, opposite Sally FIeld, Rachel Griffiths, and Matthew Rhys. Then, in 2014, Flockhart appeared in Full Circle as a mob boss in the show's second season, which aired in 2015.

With a steady stream of work and an impressive resumé to show for it, you'd think the actress would be considering some time off. But not Flockhart! Instead, the actress, who has been married to Harrison Ford since 2010, continues to prove that age is just a number. Showing no sign of stopping, we can't wait to see what's the future holds for the talented actress.

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Cheers to Calista on her birthday!