Joosten, clutching the first of her two Emmys, which she won in her 60s. (Fred Prouser/Reuters)

But the recent deaths of two well-known figures served as a reminder that the entertainment industry’s youth-is-king rule, like all rules, occasionally does get broken.

On Saturday, character actress Kathryn Joosten — best known as the ever-faithful Mrs. Landingham on “The West Wing” and the cranky yet sympathetic Karen McCluskey on “Desperate Housewives” — died of lung cancer at the age of 72; the next day, “Family Feud” host Richard Dawson died of esophageal cancer at age 79.

Career-wise, the two traveled different paths, but they shared one thing in common: The successes that made them famous didn’t come their way until both were over 40.

Dawson was a known actor and personality in his 20s and 30s, thanks to stints on “Hogan’s Heroes” and “Laugh-In,” as well as “Match Game.” But the gig that ultimately defined him was as the smooth, smoochy host of “Family Feud,” a job that began in 1976, when he was 43.

Joosten’s case, as many of her obituaries noted, was even more striking; she was 42 when she left her profession as a psychiatric nurse and started acting full-time. She moved to Los Angeles to pursue her dream at the age of 55. Ten years later, at 65, she won the first of her two Emmy Awards.

That’s an inspiring narrative. But what’s even more inspiring is that Joosten is not alone in her industry, even if all those Demi Lovato magazine covers and OMG-peppered celebrity blogosphere comments often make us forget that. Many accomplished actors and artists didn’t make it big, or even get their start, until they were at or near what we typically think of as midlife.

John Mahoney, the man who occupied memorable roles in “Moonstruck,” “Say Anything...” and on TV’s “Frasier”? He left a career as a medical journalist to become an actor when he was almost 40.

Susan Boyle sang famously about “dreaming a dream” on “Britain’s Got Talent” a few days after her 48th birthday. Now, at 51, she’s a multi-millionaire who recently performed during the queen’s Diamond Jubilee Pageant.

Although many knew who Jon Stewart was before he landed on “The Daily Show,” he didn’t achieve household-name status until, at age 37, he became America’s premier political satirist.

Oh, and George Clooney? You’ve probably heard of him. He didn’t break out big until he started treating patients on “E.R.” at the age of 33, and, arguably, didn’t become a bona fide movie star until he appeared in Steven Soderbergh’s “Out of Sight” when he was 37.

Yes, dewy faces and legs devoid of varicose veins are still the norm in celebrity-land. That’s the circle of pop culture life, the one that keeps the rising-star-osphere spinning and allows preteens to continue rolling their eyes at their parents for not knowing who Carly Rae Jepsen is. (Pssst... she sings “Call Me Maybe,” that pop confection that has already permanently implanted itself in your brain and will remain there for the entire summer.)

But Joosten, Dawson and others prove that it is still possible after a “certain” age to figure out what your signature something is and go do it. Is it rare? Yes. But it is possible. In a culture that, for better and worse, is often led by celebrity example, that’s reassuring to know.

After all, if people have managed to do it in Hollywood, the land where the repair of broken dreams usually involves a few hits of Botox, it can be done anywhere.