The Poosh founder posted clips from the celebrations after Reign turned 9 on Thursday.

Kourtney Kardashian Barker is celebrating Reign’s birthday!On Saturday, the Lemme co-founder, 44, shared clips from son Reign Disick’s epic 9th birthday party — complete with bouncy castles and a doughnut cake —  as she revealed that he “planned” the celebrations himself.

“Happy birthday to my Reigny,” Kardashian captioned the first Instagram Story video she posted, which played along to Michael Bublé’s “Holly Jolly Christmas” song.

Kardashian posted footage from Reign’s birthday party which he “planned”.

KOURTNEY KARDASHIAN/INSTAGRAM

In the clip, The Kardashians star filmed a towering lit-up Christmas tree inside her house before heading outside to where a table filled with colorful gift bags stood in front of a roaring fireplace. Nearby, was a drinks bar set up by the gourmet company Cappuccino Man.

A following clip showed kids playing on three giant bouncy castles outside during the party, one of which was a Millennium Falcon set-up from the Star Wars movie series.

“He planned the party,” Kardashian wrote in the caption, referring to Reign and revealing that her son had been very involved in deciding the events of the special celebration.

The birthday celebrations included a doughnut birthday cake display.

KOURTNEY KARDASHIAN/INSTAGRAM

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Also showcased at the party was a three-tiered iced doughnut display with candles perched on top, serving as Reign’s birthday cake, and a Raising Cranes Chicken Fingers food truck.

Kardashian has had a busy week of birthdays in the family, as sons Reign and Mason both celebrated theirs — turning 9 and 14 respectively — on Thursday.

There was also a chicken fingers food truck at the party.

Kardashian shares sons Reign and Mason with ex Scott Disick, along with daughter Penelope, 11. The Poosh founder welcomed her fourth child and first with husband Travis Barker, son Rocky, last month.

Scott, 40, paid a birthday tribute to his sons on Thursday as he posted a photo of silver balloons propped up in a lounge area, spelling out, ‘HAPPY BIRTHDAY M&R!’ referencing Mason and Reign.

“Happy birthday boys! You make my life better everyday!” Disick wrote in the caption.

Kardashians’s latest post comes after she shared her getting into the early holiday spirit in November.

The Hulu star declared that “elf season has begun” in her Instagram Story as she showed off a homemade festive elf display featuring four sledding Elf on The Shelf dolls, including one of newborn Rocky.