They remained friends throughout his ill-fated relationship with Angelina Jolie.

And eagle-eyed onlookers spotted Brad Pitt, 55, sneaking past the paparazzi as he joined the stars at ex-wife Jennifer Aniston

Actor Brad, who’s reportedly been quietly dating Charlize Theron since January, went incognito in a flat cap as he rushed inside Jennifer’s favorite West Hollywood spot, the historic Sunset Tower.

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Time to celebrate: Jennifer Aniston partied in style Saturday night as she celebrated her 50th birthday with an exclusive party

Still Friends: Brad Pitt, in flat cap, center, snuck into the star-studded bash, which was held at West Hollywood's Sunset Tower
He wasn’t alone, with stars including Katy Perry and boyfriend Orlando Bloom, chat show host Ellen DeGeneres, Gwyneth Paltrow, Barbra Streisand, Jason Bateman and Kate Hudson joining the celebrations.

Jennifer, whose birthday falls on February 11, attended the soirée in eye-catching style, stepping out in a stylish all-black jumpsuit with criss-cross detailing on the back.

With her golden locks styled in voluminous waves and her makeup applied in typically impeccable style, the star looked relaxed and happy as she was feted by her famous friends, as well as her actor dad John Aniston.

Stepping out in style: Jennifer, whose birthday falls on February 11, attended the soirée in eye-catching style, stepping out in a stylish all-black jumpsuit with criss-cross detailing on the back

Tress-ed to impress: With her golden locks styled in voluminous waves and her makeup applied in typically impeccable style, the star looked relaxed and happy as she was feted by her famous friends 

The way they were: Jennifer and Brad Pitt were one of Hollywood's most glamorous. Pictured in 2004, a year before they split

Taking the plunge: Hollywood actress Jennifer's eye-catching ensemble of choice boasted a deeply plunging neckline

Hat's the way to do it: The star's former husband Brad went incognito to the high-profile bash, stepping out in a driver's cap

Hat's the way to do it: The star's former husband Brad went incognito to the high-profile bash, stepping out in a driver's cap

Hat's the way to do it: The star's former husband Brad went incognito to the high-profile bash, stepping out in a driver's cap

Tabloid stars: Brad and Jennifer quickly became the ‘it’ couple of the early 2000s, with their every move making headlines. Two years after they met, Aniston and Pitt married

Shock split: After several years of being celebrated as one of Hollywood's most glamorous couples, Jennifer and Brad shocked fans when they announced that they were divorcing in 2005 
Also among the attendees was George Clooney, who arrived with his glamorous wife Amal. Jennifer has long been friends with George and visited him and Amal at their lake house in Como last summer.

During an appearance on The Ellen DeGeneres Show, the Friends star revealed how incredible it was to see George become a father.

‘It’s amazing to see him with children. That is what we talked about, that anything can happen,’ she told the host.

After several years of being celebrated as one of Hollywood’s most glamorous couples, Jennifer and Brad shocked fans when they announced that they were divorcing in 2005.

Support from her famous friends: Also among the attendees was George Clooney, who arrived with his glamorous wife Amal 

You've got to hand to them: The couple, who tied the knot in a romantic ceremony in Venice, exited the bash holding hands 

Effortlessly glamorous: Mother-of-two Amal, who was raised in the UK, cut a glamorous figure in a purple camisole dress

Golden girl: Amal accessorised with a pair of oversized gold hoop earrings at the exclusive party with her famous husband

Golden girl: Amal accessorised with a pair of oversized gold hoop earrings at the exclusive party with her famous husband

Close pals: Jennifer has long been friends with George and visited him and Amal at their lake house in Como last summer

Belly laughs: The photogenic twosome were in high spirits as they laughed raucously while being whisked away in their car

Daddy cool: During an appearance on The Ellen DeGeneres Show, Friends star Jennifer revealed how incredible it was to see George become a father to his twins, Ella and Alexander

Special guest: Gwyneth Paltrow was also among the long list of A-listers lucky enough to land an invitation to the gathering

It's all in the accessories: Wrapping up in a stylish camel coat, the actress accessorised with a chunky gold pendant necklace
The two began dating after meeting on a blind date their respective agents set up in 1998. They quickly became the ‘it’ couple of the early 2000s, with their every move making headlines.

Two years after they met, Jennifer and Brad tied the knot during a romantic ceremony in Malibu, California. Their marriage ended on January 5, 2005. The couple announced that they had ‘formally’ separated.

It soon emerged that he had begun a relationship with Angelina Jolie, with the actress later confirming years later that they fell in love while filming Mr And Mrs Smith in 2003, while he was still married to Jennifer.

Throughout his 11-year relationship with Angelina, tabloid stories regularly emerged that Brad was still in contact with Jennifer, seeking advice from his former wife despite his new love’s objections.

Need for speed: The pop superstar arrived with her boyfriend Orlando Bloom, who rode his gray Husqvarna motorcycle

Denim: British heartthrob Orlando wore jeans and a blue fleece-lined jacket, but jeans and a pair of brown boots to the party

She's got sole! Katy stood-out with her eye-catching footwear, sporting off-white trainers with dozens of shimmering beads

Cropped: The California Girls hitmaker styled her platinum blonde locks into a cropped quiff and added a touch of glamour with silver, shimmering earrings. Katy topped off the look with a black handbag and a leather coat

Keeping it simple: The lovebirds were casually-dressed for their outing to the exclusive soiree

Easy riders: The stars appeared to be the only ones who opted to ride into the bash on a motorcycle, as opposed to in a car
And it seems that following Brangelina’s divorce, Brad may well have renewed his friendship with his ex.

On Saturday, the exes had plenty of mutual friends to celebrate with. Katy Perry and Orlando Bloom turned heads as they arrived at Jen’s party on his gray Husqvarna motorcycle.

Orlando wore jeans and a blue fleece-lined jacket, while Katy showed off her trademark quirky sense of style, Katy donned a black, pleated leather-inspired jumpsuit.

She stood-out with her eye-catching footwear, sporting off-white trainers with dozens of shimmering beads.

The California Girls hitmaker styled her platinum blonde locks into a cropped quiff and added a touch of glamour with silver, shimmering earrings. Katy topped off the look with a black handbag and a leather coat.

A-lister: Oscar-winning actress Reese Witherspoon added her name to the A-listers who were in attendance on the night

Tumble: Reese's night came to a bit of a messy end, as she was seen falling while making her way down a short flight of stairs

Mustering a smile: The star was able to a muster up a smile after making her way to the backseat of a chauffeur-driven vehicle

Friends in high places: Screen star Demi Moore also attended the party, held at the popular celebrity haunt the Sunset Tower

Typically stylish: The actress looked typically stylish in a green dress, which she wore under a grey coat with black boots

Stand out: Accessorising with a grey clutch bag and black-rimmed spectacles, the mother-of-three stood out from the crowd

Low-cut: Oscar-winning actress Sandra Bullock also put in an appearance, wearing a low-cut black dress under a red top

Elegant: Jennifer's former Friends co-star Lisa Kudrow looked elegant and low-key in a black top and jeans with a juster jacket

Couple's night out: Christina McLarty and David Arquette (L-R) donned brown ensembles to the bash

Couple's night out: Christina McLarty and David Arquette (L-R) donned brown ensembles to the bash

Having a laugh: Isla Fisher and her British comedian husband Sacha Baron Cohen shared a laugh as they made their exit

Fashion maven: Isla looked the epitome of style in a white bardot star-print dress

Fashion maven: Isla looked the epitome of style in a white bardot star-print dress

Designated driver: Sacha looked dapper in a blue suit as he drove Isla home after the festivities 
It was a Big Little Lies night out for Reese Witherspoon and her co-star Laura Dern as the pair were among the many celebrities who attended the star-studded bash.

Reese undoubtedly had a fantastic night at the Sunset Tower Hotel as she was spotted looking slightly bleary-eyed after leaving the party.

The Legally Blonde star, 42, was radiant as ever for the evening, donning a black mini-dress. Wrapping up in a matching faux-fur coat, the actress added height to her frame with a pair of black, strappy heels.

Letting her blonde locks hang loose down her shoulders, Reese looked in high spirits as she departed her famous friend’s soirée.

So in love: Actress Kate Hudson and her beau Danny Fujikawa looked as loved up as ever as they made their exit from the bash

Romantic: The couple, who recently welcomed the birth of their daughter Rani Rose, held hands as they stepped out together

Shimmer: The Almost Famous star looked glamorous in a shimmering full-length gown, over which she draped a black coat

Flattering look: The mother-of-three styled her golden locks in a half-updo, while her makeup had a flattering dewy finish

All that glitters...: Iconic supermodel Cindy Crawford looked as chic as ever, arriving at the event in a glittering black gown

Joining the festivities: The supermodel attended the bash with her husband Rande Gerber (R)

Joining the festivities: The supermodel attended the bash with her husband Rande Gerber (pictured)

Joining the festivities: The supermodel attended the bash with her husband Rande Gerber

Partners in style: The Illinois native was joined by her handsome husband Rande Gerber, who donned an all-black ensemble


Laura, 51, cut a glamorous figure for the evening, sporting a flowing black, leather-inspired dress which she paired with a white, long-sleeved top. Styling her tresses into loose curls, she also donned black boots and carried a matching handbag.

Chat show host Ellen DeGeneres was also spotted joining the birthday shindig, looking casually cool in tailored tracksuit bottoms with a navy bomber jacket.

During the Dumplin’ star’s appearance on The Ellen Show, the host promised a special hour-long appearance for her friend on the occasion of her 50th birthday.

Iron Man and Avengers co-star Robert Downey Jr. showed up to Jennifer’s shindig looking every bit like Tony Stark.

Casually cool: Chat show host Ellen DeGeneres was also spotted joining the birthday shindig, looking casually cool in tailored tracksuit bottoms with a navy bomber jacket

Big promise: During the Dumplin' star's appearance on The Ellen Show, the host promised a special hour-long appearance for her friend on the occasion of her 50th birthday 

Ready to hit the road: The popular television star was seen chatting away as she made her way into her waiting vehicle

Glam: Laura Dern cut a glamorous figure for the evening, sporting a flowing black, leather-inspired dress which she paired with a white, long-sleeved top. Styling her tresses into loose curls, she also donned black boots and carried a matching bag

Splashing the cash: Actor Robert Downey Jr. clutched a banknote as he prepared to leave the valet team a generous tip

Superhero in the flesh: Iron Man and Avengers co-star Robert Downey Jr. showed up to Jennifer's shindig looking every bit like Tony Stark

Tinted: Robert accessorised with a pair of tinted spectacles for the party, which was attended by a who's who of Hollywood
The acclaimed actor made one of the toasts during Jennifer’s ill-fated wedding to Justin Theroux, which ended with their separation in late 2017.

Jason Bateman, her co-star in 2010’s The Switch, stepped out of a car with a goatee, a rarity for the usually clean-shaven actor.

Kate Hudson stopped by the birthday party in a shimmering black dress. She was accompanied by her beau Danny Fujikawa, with whom she recently welcomed daughter Rani Rose.

The How To Lose A Guy In 10 Days actress recently appeared with Jennifer in the romantic comedy Mother’s Day.

Icons: There was also plenty of Hollywood royalty at the Marley & Me star's bash. Barbra Streisand and her husband James Brolin made an appearance

Purple reign: The singing and acting legend complemented her ensemble with a deep purple satin jacket and matching hat

Unmissable: Diane Keaton arrived in her trademark finger-less gloves and wide-brimmed black hat

Just the two of us: Actor Charlie Day was seen outside the popular Sunset Boulevard venue with his wife Marry Elizabeth Ellis

Happy to be there: A smiling David Arquette, a figure from Jennifer's Friends days, made a special appearance


There was also plenty of Hollywood royalty at the Marley & Me star’s bash. Barbra Streisand and her husband James Brolin made an appearance, as did Diane Keaton, who wore her trademark finger-less gloves and wide-brimmed black hat.

A smiling David Arquette, a figure from Jennifer’s Friends days, made a special appearance.

After he married her co-star Courteney Cox, the NBC sitcom’s cast famously appended ‘-Arquette’ to all of their names to poke (loving) fun at their colleague.

Tobey Maguire’s ex-wife Jennifer Meyer, who designed the Horrible Bosses star’s wedding ring from her marriage to Justin Theroux, dropped by the party as well.

Going casual: Jason Bateman, her co-star in 2010's The Switch, stepped out of a car with a goatee, a rarity for the usually clean-shaven actor

Daddy's girl: Jennifer also received some support from family, with her actor dad John Aniston putting in an appearance

Satisfaction: Rock legend Keith Richards, 75, was a surprise addition to the guest list, arriving with his wife Patti Hansen

Grin: The couple, who have been married since 1983, appeared to have a great night, as they were all smiles while walking out

Jennifer Meyer, who designed the Horrible Bosses star's wedding ring from her marriage to Justin Theroux, dropped by the party as well

Birthday girl: Hollywood beauty Jennifer appeared to be in an upbeat mood as she laughed and chatted in the back of her car

This is how she rolls: The Los Angeles-born, New York-raised star chatted with pals as she was whisked away into the night