A morning mix of entertainment headlines . . .

Stewart and Pattinson at Sunday’s Teen Choice Awards. (John Shearer/Invision via AP)

The cover story of the new Us Weekly drops a “Twilight”-related bombshell: Kristen Stewart allegedly cheated on boyfriend Robert Pattinson with her “Snow White and the Huntsman” director Rupert Sanders. Sanders is married and has two children. Us says it has photos of the two kissing last week. A source told People that Stewart is “devastated,” adding “She wasn’t having an affair with Rupert. It was just a fleeting moment that shouldn’t have happened.” Reps for Stewart and Sanders have not weighed in yet. (Us Weekly; People)

Sherman Hemsley, the actor who played George Jefferson on “All in the Family” and “The Jeffersons,” died Tuesday at the age of 74. He passed away in El Paso; a cause of death was not identified. Hemsley also starred in the hit sitcom “Amen.” His passing leaves very few surviving members of “The Jeffersons” cast; Marla Gibbs (Florence), Damon Evans (the second actor to play Lionel Jefferson) and Berlinda Tolbert (Jenny, wife of Lionel) are still with us. (Washington Post)

View Photo Gallery: Hemsley, best known for playing George Jefferson on the TV sitcoms “The Jeffersons” and “All in the Family,” and as Deacon Earnest Frye on “Amen,” has died.

Another star of a popular 1970s series, “Medical Center,” also died Tuesday. Chad Everett, who played surgeon Joe Gannon on the hospital-set series, passed away in Los Angeles of lung cancer. (Associated Press)

Trouble at the Dunphy household: The principal stars of “Modern Family” are suing 20th Century Fox to void their current contracts. Several actors — Julie Bowen, Ty Burrell, Sofia Vergara, Eric Stonestreet and Jesse Tyler Ferguson — filed the suit in the midst of negotiating their salaries; Ed O’Neill, who has been paid at a higher rate and negotiates his contract separately, joined the suit out of solidarity. Production on the popular series was to begin this week but has been put on pause. (The TV Column)

TMZ reports that Vancouver police are investigating the theft of X-rated photos from singing sensation Carly Rae Jepsen’s computer. The “Call Me Maybe” star contends that the revealing photos of her were acquired by a hacker. (TMZ)

Gangster Squad” — the mobster drama whose trailer, complete with a movie theater shoot-up scene, had been playing before “The Dark Knight Rises” — has been postponed. The Ryan Gosling/Sean Penn film, originally slated to open in theaters in September, was pushed to January. (Vulture)

Two movies for “The Hobbit” is not enough. Warner Bros. and Peter Jackson are discussig the possibility of making a third movie, making “The Hobbit” Jackson’s second Tolkien trilogy. (Hollywood Reporter)

Here’s today’s deep thought from Kim Kierkegaardashian :

After the emptiness, the shipwreck, of trying to find ourselves outside ourselves, we won the award of best female reality stars on TCA!

— KimKierkegaardashian (@KimKierkegaard) July 23, 2012