Kylie Jenner shares bikini selfie before a 'swim session' with big sister Kourtney Kardashian

Kylie Jenner posted her latest bikini selfie on her Instagram account on Sunday.

The 17-year-old reality star - whose upcoming birthday is August 10 - took to her social media pages during an outing with her half-sister Kourtney Kardashian, captioning her photo: 'Kourt and Ky swim session.' 

That same day, the youngest daughter of Kris and Caitlyn Jenner shared multiple make-up free Snapchat videos with her beloved dog Norman.

Summer swimwear: Kylie Jenner posted a bikini selfie on her Instagram account on Sunday

Summer swimwear: Kylie Jenner posted a bikini selfie on her Instagram account on Sunday

For her fun in the sun, Kylie was dressed in a black bikini top and pair of bottoms that featured side cutouts.

The rumoured girlfriend of rapper Tyga held her cell phone near her face showing her long white manicured nails and multiple gold bracelets on her wrist. 

She wore her raven coloured tresses in a messy side part and loose curls in the photo, which did not include her 36-year-old sibling.

Earlier in the day, Kylie shared some close-up videos of herself and dog Norman cuddling on her Snapchat account. 

'Kourt and Ky swim session,' Jenner captioned the photo that did not include her 36-year-old sibling (pictured on July 29)

'Kourt and Ky swim session,' Jenner captioned the photo that did not include her 36-year-old sibling (pictured on July 29)

Toughen up your look in Kylie's Acne Studios biker jacket

Kylie Jenner is turning into a serious style star just like her older sisters.

What we love about her is her eclecticism. Not only does she mix designer and high street but she's mixes up her trends too, never sticking to one signature look. We like her best when she's casual and laid back so last night's outfit is hitting the mark.

Skinny jeans and a pair of over the knee boots is one of our favorite looks and Kylie wears it well. And that very cool biker jacket is by Acne Studios a hip Swedish brand with fans in everyone from Mila Kunis to Ellie Goulding, and their boxy bikers are a particular signature of the celebrity set.

So click (right) to buy Kylie's jacket now at Barneys and join the Acne gang. We love the belt at the waist, zip details and extra pockets, plus it has a stylish structured panel at the back. Acne doesn't come cheap of course so if you want to get the look for less then shop our edit of tan bikers below and ride off into the sunset.

* PRICES MAY NOT BE AS ADVERTISED
That same day: Kylie shared some close-up videos of herself and dog Norman cuddling on her Snapchat account

That same day: Kylie shared some close-up videos of herself and dog Norman cuddling on her Snapchat account

The Keeping Up With The Kardashians star appeared to be make-up free and without her go-to lipstick in the footage. 

Kylie is allegedly set to celebrate her milestone 18th birthday in Montreal, Canada, where she'll be of legal drinking age.

Although the limit may be 21 in America, the starlet is set to receive a fee of 'more than $100,000' to host a blowout bash on August 16, six days after her actual birthday.

According to TMZ, Kylie will celebrate her milestone birthday at the Beachclub Montreal, a mini party island decked out with a pool, A-list DJs, its own beach and alcohol on offer. 

Fresh faced: The Keeping Up With The Kardashians star appeared to be makeup-free and without her go-to lipstick in the footage
Fresh faced: The Keeping Up With The Kardashians star appeared to be makeup-free and without her go-to lipstick in the footage

Fresh faced: The Keeping Up With The Kardashians star appeared to be makeup-free and without her go-to lipstick in the footage

It's claimed the teen will be paid between $100k and $200k just for showing up to the event and partying with her friends.

It's believed the club's owner, Olivier Primeau, will have Kylie flown into the bash by helicopter, where she'll land on a luxury boat that will dock next to a table flooded in bottles of champagne.

She'll also blow out the candles on a $3,000 birthday cake. 

According to the site, tickets for the event are retailing between $40 to $150. 

Lucky lady! Although the limit may be 21 in America, the reality star is set to receive a fee of 'more than $100,000' to host a blowout bash on August 16, six days after her actual birthday

Lucky lady! Although the limit may be 21 in America, the reality star is set to receive a fee of 'more than $100,000' to host a blowout bash on August 16, six days after her actual birthday

But while the reality star is planning to go large for her upcoming birthday bash, her 17th birthday was hardly birthday cake and pinatas.

Instead, Kylie was seen partying with A-list stars including sister Kendall Jenner, Justin Bieber, Chris Brown and rumoured flame Tyga, at an LA nightclub.

But while older party goers, who included rapper The Dream, were seen clutching at bottles of D'Ussé cognac, Kylie looked to be on her best behaviour and was never seen consuming the beverage (which costs around $50 a bottle). 

But the teen certainly didn't need alcohol to get her in the party spirit as a video obtained by TMZ showed the Keeping Up With the Kardashians star dancing to 50 Cent's In Da Club in a black dress, with a daring thigh high split. 

Not yet 21: Kylie (far right) celebrated turning 17 at an LA club with (from left) Tyga, Justin Bieber and The Game, the last two who were holding bottles of hard liquor

Not yet 21: Kylie (far right) celebrated turning 17 at an LA club with (from left) Tyga, Justin Bieber and The Game, the last two who were holding bottles of hard liquor

The following morning thanked her guests for celebrating with her, gushing: 'thank u everyone & T for the cake & JB for singing happy bday to me. I love u guys.'

Speaking to E! earlier this month, Kylie revealed she was planning a huge party and a holiday with her friends to celebrate her 18th birthday.

She said: 'The first thing I want to do is maybe have like a birthday party and then maybe go on a trip with just my friends.

'I'm legal, so I can go on a trip legally without a chaperone, so that'll be fun, just a girl trip.' 

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