Age is a sensitive topic for actresses. Jessica Chastain has gone on the record saying that she will never reveal her age because she's an "actress." (It's widely speculated she is 35 years old.) Isabelle Huppert chided me during an interview for asking a question about her "longevity" in the business.
But age doesn't faze Mary Steenburgen, the actress who famously got her start after being discovered by Jack Nicholson in the reception room of Paramount's New York office only to be cast later as the female lead in his second directorial effort, Goin' South (1978), her first film.