Warren Beatty and Annette Benning and their Newfoundland
Beatty (b. 1937) and Benning (b. 1958) are American actors, and constitute one of Hollywood's more famous power couples, both having had distinguished, high-profile, multi-award-winning film careers for decades. They have been married since 1992.
And they are indeed Newfoundland owners. The following photo accompanied a Feb 13, 2024, New York Times article on celebrities and their favorite leisure activities, with Benning's being hiking:
(And yes, I am presuming the Newf in the photo was Benning's, not a random dog she and the photographer encountered on the trail.)
The Times article does not mention the dog, but a profile of Benning that appeared on AARP's website in 2019 does:
"She and Beatty, 82, are newish empty nesters. It's just the two of them and their 130-pound Newfoundland "puppy," Scout, since Ella, the youngest of their four children, left for Juilliard earlier this year."
That's the only mention of the dog, but if you want to read the entire profile, just click the link right above the quoted passage.
