A morning mix of entertainment headlines...

Chris Lighty, gone at age 44. (Jim Cooper/AP)

Chris Lighty — the manager who guided the careers of hip-hop and pop stars like A Tribe Called Quest, LL Cool J, Diddy, 50 Cent, Missy Elliott and Mariah Carey — was found dead Thursday of what authorities said was a self-inflicted gunshot wound. According to the New York Daily News, the 44-year-old founder of Violator Management shot himself outside of his home in the Bronx following an argument with his estranged wife. In a tribute to Lighty for NPR, former Billboard and Vibe editor Danyel Smith writes: “Yes, Chris Lighty made history. He helped make hip-hop. He was a success story. He was a sweet and brilliant man. But there will be no more knowing of him — the complexities, the simple s—, nothing. The man in the liner notes, the kid backstage, the dude counting the show money, the father with his children. It’s beyond tragic. Everybody’s Baby Chris is gone.” (New York Daily News; NPR)

The L.A. coroner's office has determined that Sage Stallone, the 36-year-old son of Sylvester Stallone, died because of a heart condition. The younger Stallone was found dead in his home on July 13, but a cause of death had not been determined. The coroner’s report, released Thursday, said a heart condition caused a blockage of the arteries. (Associated Press)

Robin Roberts has lost her mother. George Stephanopolous announced Friday on “Good Morning America” that Lucimarian Tolliver Roberts, the mother of his “GMA” co-host, died Thursday at the age of 88. Roberts had begun her planned medical leave a day early to spend time with her mom. Roberts is taking a leave of absence from the ABC morning show to undergo a bone marrow transplant. (People)

In happier news, Tori Spelling and Dean McDermott welcomed their fourth child into the world on Thursday. Their son is yet another in a string of recent celebrity babies with totally normal names: Finn Davey. (Associated Press)

In other “90210” news, the National Enquirer started a rumor that a lot of Gen Xers really wanted to believe: that Jennie Garth and Luke Perry had fallen in love. Gossip Cop and Us quickly debunked that flagrantly false-sounding story, then RumorFix chimed in to note that Kelly and Dylan are actually working on developing a TV sitcom together. Which is not as exciting as imagining them snuggling by a fire in real life while the song “Damn I Wish I Was Your Lover” plays on the soundtrack in our imaginations, but it’s okay, I guess. (Gossip Cop; Us; RumorFix)

Bruce Willis wants us all to know that he is really upset about Kristen Stewart and Robert Pattinson’s break-up, as in upset enough to do a “Die Hard” parody based on it during the “Late Show With David Letterman. ” (Late Show)

FYI: Judy Greer’s Kitty will show up in the new episodes of “Arrested Development,” as she confirmed earlier this week via a tweeted image. (Via Vulture)

Guess what I’m doing today....... twitter.com/missjudygreer/…

— judy greer (@missjudygreer) August 30, 2012

Another FYI: if you pair the music from “Inception” with Michael J. Fox’s werewolf transformation in “Teen Wolf,” it seems kind of Oscar-worthy. Kind of. (Via Buzzfeed)