Mason Disick has joined InstagramCredit: Instagram/masondisick

He shared his first three posts on the platformCredit: Instagram/masondisick

Mason posed in never-before-seen pics with his brother Reign and sister PenelopeCredit: INSTAGRAM/MASONDISICK

But Mason, 14, made his social media debut with a brand new Instagram account, created on Saturday night.

The reality star shared three posts to kick things off, starting with a solo shot on the front porch of a lakefront cabin.

In the snaps, the TV personality showed off his trendy style in army green parachute pants paired with a black Off White T-shirt.

He covered his face with a blue and gray baseball cap, which he pulled down to show off edgy silver rings on his fingers.

The second photo of the first post was taken in the same location but showed off Mason’s back.

He flaunted a silver watch and black Fila sneakers in the shot.

Mason nodded to his aunt Kylie Jenner’s ex-boyfriend Travis Scott in the post by adding the rapper’s song with Future, Type S**t.”

The teen left the post captionless and limited comments to only two from his family.

ALL GROWN UP

His aunt Khloe Kardashian, 39, wrote, “I can’t believe this is happening,” while his aunt Kim, 43, agreed, “You’re really on Instagram,” with an emotional emoji.

Mason’s second post showed him standing against a white wall with three of his friends.

The boys all held shopping bags from Jaded London and looked off in different directions.

Scott Disick’s son again showed off his personal style in baggy jeans, a black Supreme hoodie, and brown sneakers.

FAMILY TIME

A second slide showed him walking down a city street next to his sister Penelope, 11.

Mason sported a gray fur Supreme jacket while his sister matched in a fur cheetah print jacket and jeans.

The final photo of the carousel showed the brother-sister duo indulging in ice cream.

Little Penelope wore a cream-colored pullover with her brunette hair slicked back with a matching headband.

She carried a black purse on her right arm as she scooped the frozen treat into her mouth.

Meanwhile, Mason had on a green denim jacket with a huge waffle sundae in his hands.

He captioned the second post, “Fam.”

MASON’S BUDDIES

The TV star’s third and final new post was a slew of mirror selfies.

In the first, Mason posed next to his little brother Reign, 9, in a tan bathroom with a filthy mirror.

Both kids sported T-shirts, hoodies, and baggy pants and wore serious expressions on their faces.

Kourtney’s eldest child posed with a lookalike friend in the second slide.

Mason and his buddy showed off their curly hair and similar styles in matching hoodies, his in black and the friend’s in red.

The final shot was taken at nighttime in a dark room as the teen’s friend hid his face from the camera.

The Hulu star captioned his post, “Mirror pics is all we know,” using the mirror emoji in lieu of the word.

The teen again nodded to Travis Scott, 33, by adding his song Antidote.

SOCIAL MEDIA DEBUT

Mason has already garnered over 135k followers, though he currently only follows his dad, Scott, mom, Kourtney, grandmother, Kris, and aunts Kim, Kylie, Kendall, and Khloe.

The teen also follows his uncle, Rob Kardashian, 37.

Kourtney was clearly emotional about her son joining Instagram, as she shared a message with fans regarding the news on Sunday.

The mother of four reshared her son’s first post on her Instagram Stories, writing, “My first baby is on Insta and I’m not okay,” with two crying emojis.

She also tagged Mason and added a red heart.

Kourtney shares Mason, Penelope, and Reign with her ex, Scott, and her son Rocky, who is 6 months old, with her husband, Travis Barker.

Mason shared snaps with his sister, PenelopeCredit: Instagram/masondisick

The siblings indulged in ice cream togetherCredit: Instagram/masondisick

Kourtney shares three children with her ex Scott DisickCredit: Instagram/kourtneykardash