She turned 22 on Saturday and has been wowing her fans with a series of social media updates which show her very glamorous celebrations in Portofino.
But Kylie Jenner's fans have been taking to social media to blame surgical procedures for making her look around a decade older than her years.
It's also likely that the fact that she has also achieved so much in her short life already, has also led people to think she's older than she is.
Why does Kylie Jenner look a decade older on her 22nd birthday? Fans have expressed their shock over reality star's REAL age after she admitted to having work done
Making changes: Kylie pictured in Portofino on Monday (left) compared to a picture taken in February 2012 when she was aged 15 (right)
The reality star was named Forbes' youngest self-made billionaire due to her beauty empire and she's also mother to baby Stormi, 18 months.
Kylie has admitted to experimenting with facial fillers in the past and it's fair to say her lips are much more plumped now than just a few years ago.
She first started to look different in 2014, when aged 17, Kylie started to show off a plumped pout, after getting lip fillers - she admitted this was the case a year later.
A year on, Kylie's face shape changes, due to filler injections and now aged 18, Plastic Surgeon, Alex Karidis, claims this could be down to rhinoplasty.
He said: 'Her nose appears thinner, particularly at the tip.'
Aged 19, Kylie changes her appearance with the use of heavy make-up and has said she reveals 'contouring is everything.'
The make-up mogul also claims she uses her products to alter her appearance but claims she is 'terrified' of having anything more done.
Age 5: Kylie (left) has been in the public eye from a young age - pictured with sister Kendall (right)
Age 13: Kylie pictured as a teenager before she even dreamed of having any work done
Age 14 and 15 (left and right): Kylie was starting to experiment with her look in 2011 and 2012 and was sporting more voluminous hair and false eyelashes
Age 16: Kylie sported a bold red lip but still kept things simple with the rest of her look
She told PAPER in February: 'People think I fully went under the knife and reconstructed my face, which is completely false.
'I'm terrified! I would never. They don't understand what good hair and makeup and, like, fillers, can really do. It's fillers. I'm not denying that.'
In 2015, Kylie addressed rumours that she had undergone breast augmentation and said her curvier figure was down to 'weight gain.'
Age 17: Kylie starts to have filler injected into her lips and experiments with wigs - she admitted she had started having injections a year later
Age 18 and 19: Kylie's face shape continues to change with the use of fillers (left and right) and Dr Karidis said that her nose appears thinner at the tip which could be down to rhinoplasty
Age 19: Kylie looks unrecognisable at a red carpet event in January 2017 - Karidis has said she may have given the illusion of a wider eye with an upper eyelid lift - a minor procedure
Age 18: By August, Kylie adopted a more mature look. Plastic Surgeon Alex Karidis said she has either had a brow lift or is relying on a brow aesthetician to change the shape
Age 21: The distance between Kylie's lip and nose appears smaller again, which could be down to more lip filler, or Karidis says she may have had an upper lip lift, which requires a tiny incision under the nose and wouldn't be visible with make-up - pictured in February 2019
WHAT THE PLASTIC SURGEON SAYS...
Dr Alex Karidis, Plastic Surgeon at Karidis Clinic told MailOnline:
'Kylie's admitted to having some work done and I would say she looks 26 or 27 rather than her 22 years. No doubt as a businesswoman and mother, she wants to be taken seriously and look mature. This is human nature.
'I would say Kylie's nose looks narrower at the tip so she could have had a rhinoplasty. Her brows look more arched and elevated. This could be the result of non-surgical Botox or tattooing.
'Kylie could also have had her upper eyelid opened up and she may have also had an upper lip lift.
'Both procedures are minimal but make a real difference. They leave very minimal scarring which could be covered up with make-up.'
She wrote on her website: 'No, people - I haven't gotten breast implants. Everyone is obsessed with that. Truth is, as I've gotten older, I've gained 15 pounds and my body has changed; I've definitely filled out.
'I just use the Bombshell by Victoria's Secret. It's life-changing. I've gotten all my sisters on it and all my friends...Clearly, it's like 10 times bigger - no contouring, no nothing.
'This is all padding. I think it makes your breast look great and girlie. This is it. No breast implants. No surgery. Nothing. It's amazing. So if you guys want this look, here's my secret.'
She added: 'Working with some of the best makeup artists has taught me a lot of amazing tricks to making me feel more confident and I can't wait to share them with you guys.
'"I swear there are things you can do to work on problem areas without having to think about plastic surgery. (Contouring has changed my life!)'.
After seeing the most recent pictures of her away on holiday, her fans have taken to Twitter to express their surprise that she is only 22 years of age.
They wrote: 'Idc what anyone says. Kylie Jenner is starting to look very old!'
'The first time I saw @KylieJenner I thought she's 25 or 30 yrs old coz she have a daughter and she really look matured, but she's only 22!!! 22!!! The heck next I'm turning 20 but I look like a 15.'
'Kylie Jenner turned 22 but looks at least 30 with a baby.'
'I still can’t believe Kylie Jenner is only 21, she genuinely looks like a 50yr old trying to be 21.'
Top plastic surgeon Mark Ho-Asjoe previously told Closer magazine that he believes she has had more work done than she claims and this is ageing her.
Celebrations: Kylie has been sharing lots of pictures from her trip in Portofino, from her luxury yacht
Mix and match: A snap taken in Capri showed a heavily filtered Kylie showing off plump lips enhanced with make-up
She's done a lot: The reality star was named Forbes' youngest self-made billionaire due to her beauty empire and she's also mother to baby Stormi, 18 months
He wrote: 'Kylie has made herself look way beyond her years. All the surgery I suspect she's had - fillers to her lips and cheeks, a nose job and possibly some bone shaving around her jaw - is ageing her.
'Her eyes look wider, which implies she may have had eye surgery.
'If she continues with all these treatments, in 10 years time the skin around her lips will have stretched like a balloon and if she doesn't keep plumping them up the skin will be wrinkled.'
Something to say: Kylie's fans have taken to Twitter after discovering her true age - believing that she was older