Seeing double! A grown-up Kendall Jenner posts mirror image of herself wearing chic octagonal glasses during photo shoot for her new clothing line

She has only so far enjoyed a short career in the modelling world.
But thanks to her reality TV programs, Kendall Jenner is quite the pro when it comes to posing for the camera.
The 17-year-old has a new fashion line debuting on Friday and she made sure to promote her burgeoning business on Twitter.

Scroll down for video

Seeing double: Kendall Jenner has a new fashion line debuting on Friday and she made sure to promote her burgeoning business on Twitter on Thursday

She looked all grown up in a mirrored image of herself, wearing a pair of chic octagonal glasses which accessorised her black strapless dress.
With her long brown locks perfectly coiffed, her face was done up in wing-tipped eyeliner and lashings of pink lipstick.
During the shoot the brand ambassador for Seventeen Magazine still made time for some fun with older sister Khloe Kardashian on the set of her fashion shoot.

Fun loving sisters: Kendall Jenner and Khloe Kardashian on the set of a photo shoot in Los Angeles, on Thursday

Kendall was shooting some fashion stills for her clothing line Kendall & Kylie with PacSun in Los Angeles.

The petite television personality shares the line with younger sister Kylie Jenner.

In promotion of her new brand Kendall tweeted, on Thursday: '1 Day left until our Summer Collection!!!! Who's ready?!?'

Young entrepreneur: Kendall informed fans of her debut as a fashion designer

But the young woman was not all business as she posed for casual snaps with her older sister Khloe.

And Khloe, 28, appeared to be delighted to spend some quality time with her little sister.
She wrote as a caption for an Instagram picture of the two posing on the hood of a white car: 'I like bad b*****s that's not my only problem boo.'

The playful post referred to the cool posture her younger sister had assumed for the impromptu snap.

Adorable: The two girls clearly enjoyed their day together

Khloe kept it relaxed and easy in a pair of torn skinny jeans and a form-fitting white top.

The older sister had also donned strappy open-toed high healed sandals and aviator sunglasses for the warm day.

The younger of the two went for something a little more summery in her attire.

The fashion designer wore an elegant white summer dress for the sun-filled afternoon in California.

Befitting her age the young lady kept her feet snug in a pair of White Converse All Stars high tops.

But putting a more mature edge on her appearance the model adorned her face with bright red lipstick.

Dance moves: Kendall lightheartedly posed with make up artist Rob Scheppy behind the scenes

Later the Forever 21 model posed in cut-off jean shorts and an American flag cross-strapped tank top.

The beachwear was displayed in a snap of her and make up artist Rob Scheppy miming dance moves for the camera.

The Instagram post was accompanied by the caption: 'me and @robscheppy gettin our groove on at the shoot #PacsunBaby.'

Booty posing: The 17-year-old posted a snap of her older sister Khloe's curvy bottom half

But the fun and games soon included Twitter references to Khloe's famous curves.

One snap had Khloe backing up her voluptuous derriere into her younger sister with the caption: 'big booty...'

And later Kendall shared on the video site Keek a five second clip of Khloe bouncing her pert bottom to her younger sister's delight.

Kendall could be heard saying 'Go!' signalling to her sibling to dance.

But throughout the performance the teenager's laughter could be heard ending in the compliment: 'I like that.'

The caption for the video was just as playful: 'she like bad b*****s that's her f'ing probleemmmm.'

Sister love: The brand ambassador for Seventeen Magazine posted a snap with the caption 'my gumdrop' affectionately referring to Khloe

In another less provocative Instagram posting Khloe shared a snap of the two with heads pressed together with the simple caption: 'Butter bag.'

The love the two girls share for each was more than obvious throughout the day's shenanigans.

And even more telling was how much pleasure the sisters clearly derive from each others company.

Fashion Partner: Kylie Jenner was also on set for the photo shoot to promote the clothing line she shares with her older sister Kendall