Star Sightings: Kaia Gerber Celebrates Her Sweet 16, Justin Bieber Makes a Surprise Appearance & More!

Kaia Gerber 16th Birthday
Sara Jaye Weiss

What a sweet Sweet 16!

As the face of Daisy Marc Jacobs, it was only appropriate that Kaia Gerbercelebrated her big birthday with an arrangement of daisies that spelled out her name. The stunning model, who's looking more and more like her mom, Cindy Crawford, every day, posed in front of the pretty flowers with her pup. Gerber turned 16 on Sept. 3.

Kaia Gerber 16th Birthday
Sara Jaye Weiss

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Her brother, Presley Gerber, also got a birthday on this week, albeit a friend's. Along with pals Cameron Dallas and G-Eazy, the 18-year-old model had dinner at TAO Los Angeles on Aug. 29, enjoying crispy rice tuna, chicken satay, temple salad and the Mandarin orange chicken before indulging in the restaurant's signature birthday dessert, a giant fortune cookie. Shawn Mendes was also at the Hollywood hot spot, celebrating his friend's birthday in a sky box.

Justin Bieber was also in the mood to party! He made a surprise appearance at the L.A. premiere party for Rory Kramer’s new MTV show, Dare to Live, on Aug. 29.

The Canadian singer had previously FaceTimed the videographer congratulations on his show, but said he wouldn't be able to make it to the launch. "Then at the party, Rory was in the dance circle, spun around and JB was there with a smug smile on his face!" a source told ET. "Rory threw up his hands and hugged Bieber when he saw him and then brought him to say hi to his parents.”

The eyewitness adds that the Biebs -- who knew Kramer's parents from staying with them at his lake house -- was dancing and having a great time. Though he didn't stay very long, he was reportedly "really sweet and cool to everyone."

Justin Bieber and Rory Kramer
Rich Polk

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Always looking to learn more about the art of making food, model-turned-cookbook author Chrissy Teigen invited Chef Chris Ford of the Beverly Wilshire Hotel and Crateful Chef Luciano Pellegrini, to her Beverly Hills, California, home for two separate explorations into the artistry behind their creations.

Ford taught the gorgeous foodie the secrets of pastry embellishment, constructing versions of his apricot-and-pistachio cheesecake, while Pellegrini gave Teigen and her husband, John Legend, an Italian cooking class, helping them to create fresh pasta stuffed with Fontina Cheese and Urbani Black Truffles.

Chrissy Teigen and Chef Ford
Eclat Public Relations

Over in Las Vegas, Miles Teller had a great time during his pal's bachelor party weekend. His crew kicked off the festivities on Sept. 1 at Encore Beach Club, where his crew sipped on Tito's vodka cocktails, Don Julio 1942 and beer in a luxury bungalow. Teller stopped to say hello to DJ Kygo, who was spinning at the afternoon party, before he and his boys headed out to XS Nightclub to see The Chainsmokers. The next night, they hit up Intrigue Nightclub, taking over the backstage area close to where RL Grime was spinning.

The Whiplash star will be having his own bachelor party soon enough -- he popped the question to his longtime girlfriend, Keleigh Sperry, last month during a safari adventure in South Africa.

DJ Kygo and Miles Teller
Michael Kirschbaum

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A ton of other stars have also spent time in Sin City recently. 

Abigail Breslin picked up some goodies inside the pawn shop-inspired retail store at Beauty & Essex in The Cosmopolitan of Las Vegas on Aug. 28. Shopping with her boyfriend and a few friends, the Scream Queens star settled on a Schecter guitar and Gone With the Wind doll.

Dave Chappelle wrapped up Kevin Hart's Hartbeat Weekend on Sept. 3 with a sold-out show at The Chelsea inside The Cosmopolitan of Las Vegas. Usher, who opened Hart's festival with a concert two days earlier, Jermaine Dupri, Tyga and Donnell Rawlings all took in the stand-up set.

Dave Chappelle at Hartbeat
Brenton Ho/Kabik Photo Group

On the opposite coast, Charlie Puth kicked off Global Citizen and Cadillac's Accelerator Series with an intimate performance at Cadillac House in New York City on Aug. 29. Andra Day will be the next performer in the series on Sept. 19.

Charlie Puth
Theo Wargo/NBC/Getty Images for Global Citizen

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Chappelle wasn't the only star wrapping up summer by taking the stage. French Montana ​helped launch CÎROC French Vanilla with a performance at Create Nightclub in Hollywood on Aug. 31.

French Montana
Michael Simon/

Cardi B performed for a sold-out crowd at Parq Restaurant & Nightclub in San Diego on Aug. 25.

Cardi B
Sergio Lopez

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And Meek Mill, 21 Savage, Pusha T and PnB Rock were all spotted in the D'USSÉ lounge between performances at the Made in America festival in Philadelphia this past weekend, while Fabolous was spotted drinking the cognac brand as he watched JAY-Z's headlining set.

Fabolous Made in America
Shareif Ziyadat

Meanwhile, Ashley Tisdale was all about the athleisurewear trend, running errands in West Hollywood, California, on Aug. 30 while sporting fitness gear from Rise Nation studio. 

Melissa Gorga opted for the boho trend while out in New York, donning a very summery navy blue racerback dress by Gypsy05.

Melissa Gorga in Gypsy05
Michael Simon

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On the beauty front, Giada De Laurentiis has partnered with Philosophy to talk beauty tips and their new Ultimate Miracle Worker retinol pads.

Giada De Laurentiis

With the end of summer came a whole lot of sightseeing before the autumn temps kick in, though many celebs were traveling for work.

During her trip to Australia for a photo shoot in late August, Elizabeth Olsen stayed at designer hotel QT Melbourne -- and rocked this gorgeous Dior outfit!

Brian Austin Green took his 15-year-old son, Kassius, to the Hard Rock Hotel Rivera Maya for a father-son getaway. The duo fueled up on sushi and stir-fry at the property's Zen restaurant before ziplining, kayaking, and tightrope walking. They did relax in between all that activity, getting massages at RockSpa and lying out by the water.

Brian Austin Green and son
Hard Rock Hotel Rivera Maya

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Jesse Eisenberg stayed at the Trumbull & Porter Hotel, owned by Leo Lee, while in Detroit, Michigan, last month, while Conan O'Brien checked into the Presidential Suite at Dan Tel Aviv for his visit to Israel.

Not letting those summer days go without one last trip, Real Housewives of New York City star Carole Radziwill attended the ribbon-cutting celebration of sbe’s Katsuya Baha Mar in Nassau, Bahamas, on Aug. 29.

Carole Real Housewives of New York
Seth Browarnik/

Check out even more must-see star sightings in the gallery below!

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