Kelly Osbourne celebrated her 40th birthday on Oct. 27, spending time over the weekend with her famous family at a party at The Bird Streets Club in West Hollywood.

The outing was a fitting celebration for the milestone birthday, as Kelly originally rose to fame with her father, legendary rocker Ozzy Osbourne, mother Sharon and brother Jack at her side.

The star, who has tried her hand at a number of careers in the entertainment industry, of course, looked remarkably different from how she did when the family's reality show, "The Osbournes," premiered in 2002. She was only 17 when the show began.

KELLY OSBOURNE HOPES SHE'S ‘EMBALMED’ HER BODY WITH DRUG, ALCOHOL USE SO SHE CAN'T GET CANCER

A split image of Kelly Osbourne in 2002 and now

Kelly Osbourne, pictured in 2002 (left) and now (right). (SGranitz/WireImage; Rachpoot/Bauer-Griffin/GC Images)

In photos of her arrival at the venue, Kelly was seen wearing a form-fitting floor-length gown. The dress also had long sleeves, with a low neckline that showcased her cleavage.

Her hair, which is blonde rather than the purple she usually seems to favor, was worn in an updo and tied with a black ribbon. She kept her makeup more on the neutral side, with black eyeliner and nude lipstick.

A photo of Kelly Osbourne

Kelly Osbourne is seen arriving for her 40th birthday celebration at The Bird Streets Club in West Hollywood on October 27, 2024, in Los Angeles, California. (Rachpoot/Bauer-Griffin/GC Images)

The look was considerably more classic than viewers may remember from the early days of her time in the spotlight. Then, Kelly dressed in a much more alternative fashion, at times having black, blonde or red hair, and typically wearing very heavy makeup.

A photo of Kelly Osbourne in 2002 with short red hair

Kelly Osbourne during the 2002 MTV Movie Awards. (Jeff Kravitz/FilmMagic, Inc)

She also looked slimmer than ever, after revealing earlier this year that she had lost a considerable amount of weight after giving birth to her son, Sidney, at the end of 2022.

"I know everybody thinks I took Ozempic. I did not take Ozempic. I don’t know where that came from," she told Extra in April. "My mom took Ozempic."

A photo of Sharon and Kelly Osbourne

Kelly Osbourne with mother Sharon in 2020. (FOX via Getty Images)

Kelly explained, "I had gestational diabetes, and I had to lose the weight that I had gained during pregnancy, otherwise I was at a higher risk of actually getting diabetes, which I did not want. I cut out sugar and carbohydrates, and I rapidly lost weight."

She also had a non-surgical sculpting procedure done to tighten skin in various spots on her body, including on her stomach and neck.

A photo of Kelly Osbourne

Kelly Osborne is seen arriving at The CUPSHE Pool House in Beverly Hills on June 26, 2024, in Los Angeles, California. (Rachpoot/Bauer-Griffin/GC Images)

"I had the baby, and my stomach got so many stretch marks, and the skin, it looks like it lost its elasticity," she said.

The television personality told Us Weekly for this week's cover story that while she has had similar procedures and some Botox, she's never had any fillers or plastic surgery.

"I’ve always been really honest about what I’ve done and haven’t done," she said. "I’ll do injections all day long, but I’ve never done filler. Everyone’s like, ‘You’ve done too much to your face,’ and I’m like, ‘Actually, underneath all that fat, I was actually alright-looking.’ My face changed shape when I lost weight."

Kelly Osbourne at the grammys

Kelly Osbourne attends the 66th Grammy Awards at Crypto.com Arena on February 4, 2024, in Los Angeles, California. (Kayla Oaddams/WireImage)

When asked whether she might get plastic surgery in the future, she answered, "Oh my God, I’m already there. There are certain things, like I don’t want a flicky neck, so I'll get that cleaned up. I don’t want jowls, which I feel like I’m starting to get. There’s a way to do it gracefully. I don’t wanna change my face. I want to get my t--s done. They look droopy and saggy, but I’m too scared. I’m already in pain, and what if it goes wrong?"

She also told the publication that she's not currently focused on her weight, and she doesn't work out. "It’s about making the healthiest choice in that moment, and sometimes I don’t make the healthy choice. But if I fall off, I get right back on again," she said.

The star has said that she has lost 85 pounds since undergoing gastric bypass surgery in 2020.

kelly osbourne against blue background

Kelly Osbourne attends the Dior Men's Spring/Summer 2023 Collection on May 19, 2022, in Los Angeles, California. (Matt Winkelmeyer/Getty Images)

A photo of Kelly Osbourne in 2020

Kelly Osbourne in 2020 at the 28th Annual Elton John AIDS Foundation Academy Awards Viewing Party. (Jamie McCarthy/Getty Images for EJAF)

In a 2022 episode of the "Hollywood Raw" podcast, she said, "I had surgery; I don’t give a f--- what anyone has to say. I did it, I’m proud of it. . . . I did the gastric sleeve. All it does is change the shape of your stomach. I got that almost two years ago. I will never, ever, ever lie about it, ever. It is the best thing I have ever done."

Kelly also said she had to do "stand-alone therapy" for a year ahead of the surgery, explaining that the procedure "cuts out this hormone that if you have addiction issues, it stops your craving, and it makes you not emotionally eat, which is a huge problem for me."

She added, "All it is, is a push in the right direction. It doesn’t solve all your problems. It’s not a quick fix."

Osbourne family

(L-R) Sharon Osbourne, Kelly Osbourne, Jack Osbourne and Ozzy Osbourne appear as guest presenters on MTV TRL at The Penthouse, Leicester Square on December 17, 2004, in London. (Photo by Dave Hogan/Getty Images)

While she's been open about her struggles with weight, she's also been open about her struggles with addiction — she said on the podcast that before she could get her body healthy, she had to get her mind healthy, and the first step of that was getting sober.

In a 2021 episode of Red Table Talk, Kelly admitted that her addiction first began when she was 13. After a "really bad case of tonsillitis," she underwent surgery and as she recovered, she was given Vicodin.

A photo of the Osbourne family in 2000.

(L-R) Sharon Osbourne, Kelly Osbourne, Ozzy Osbourne, Aimee Osbourne and Jack Osbourne attend 42nd Annual Grammy Awards on February 23, 2000, at the Staples Center in Los Angeles, California. (Ron Galella, Ltd./Ron Galella Collection via Getty Images)

"And that was all I needed," she remembered of taking the painkiller. "I went from having every voice in my head being like, 'You're fat, you're ugly, you're not good enough, no one likes you, you don't deserve this, people only like you because of who your parents are.' And then all of a sudden, every single voice was silenced, and it felt like life gave me a hug."

After taking Vicodin, Kelly said that she started taking another opioid, Percocet. She eventually began using heroin "because it was cheaper."

A photo of Kelly Osbourne in 2001

Kelly Osbourne attends the 53rd Annual Emmy Awards at the Shubert Theater in Los Angeles in 2001. (Donato Sardella/WWD/Penske Media via Getty Images)

At 19, she went to rehab for the first time — something she said in an episode of "TMZ Investigates: Matthew Perry & The Secret Celebrity Drug Ring" last month "was like university on how to be a better drug addict."

She added, "I'd learned so many tricks, so many things that I never even thought of from my fellow addicts that were in there. I'd also seen people threaten to leave until they got given what they wanted, whether it be Ambien for sleep or Valium for nerves — they’d end up getting it."

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Photo of Kelly Osbourne at 19

Kelly Osbourne pictured at 19, the year she went to rehab. (Mike Marsland/WireImage; Jon Kopaloff/FilmMagic)

She went to different rehab facilities seven times over the years, finally becoming sober in 2017. In 2021, she briefly relapsed, only telling her Instagram followers about the slip-up when she was already "back on track."

"I am sober today and I'm gonna be sober tomorrow, but I've learned it truly is just one day at a time," she shared on the social media site.

A photo of Kelly Osbourne

Kelly Osbourne performs at the 2005 MTV Australia Video Music Awards. (M. Caulfield/WireImage)

She told Extra at the time that she had had a "nervous breakdown" that led to her temporary lapse, explaining, "I’m that girl that when everything is going great I need to f--- it up a little and make everything a little bit worse in my life. I am an addict and had thought that I had enough time under my belt and I could drink like a normal person, and it turns out I cannot, and I will never be normal. I don’t know why I even tried it. It’s not for me, and it took me a matter of days, and I was like done, not doing this."

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Now, she's feeling grateful for everything that's led her to where she is now.

A photo of Kelly Osbourne and son Sidney

Kelly Osbourne and son, Sidney attend the 2024 Rock & Roll Hall Of Fame Induction Ceremony on October 19, 2024, in Cleveland, Ohio. (Kevin Mazur/Getty Images for The Rock and Roll Hall of Fame)

"I am just so grateful for every mistake I made, for every lesson learned, for all of it. I have such an incredible life," she told Us Weekly, later adding, "Turning 40 is the opportunity to be the real me and say goodbye to all of the past. I get to start again. I used to carry around the shame of being an addict everywhere with me, and it was a heavy burden to bear."

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