The eldest Kardashian sibling treated Mason with a trip to the famous amusement park in California on Tuesday (10 December), ahead of him turning four years old on Saturday (14 December).
And although the outing was for her little one, it looks like Kourtney had a lot of fun during her Disney filled day too!
The 34-year-old reality star popped on a pair of gorgeous gold sequin mouse ears for the outing and posed for couple of selfies, which she swiftly uploaded on Instagram.
One of the snaps sees Kourtney teaming her Mickey ears with a pair of speckled Ray-Ban sunglasses. She wrote: "The magic today began with my #mickeymouse printed #raybans #disneyland".
Later on, she posed for another picture with a friend and took off her shades to reveal a surprisingly fresh, make-up free face.
Kourtney captioned the snap: "Mason's birthday week!!! We're at Disneyland!!! Ahhh!!! #BFFlife #Mommylife #disneyland".
As well as taking selfies, the brunette mother-of-two posted various pictures of the theme park's magical scenery and stayed late enough at Disneyland to watch the famous fireworks in the evening.
We wonder if she brought baby Penelope along for some fun at the resort too?!
Meanwhile, Kourtney's longtime boyfriend Scott has been keeping busy lately hanging out with new BFF and Kim Kardashian's fiancé, Kanye West.
Scott accompanied Kanye to his Yeezus tour show in LA this week and even met up with Christina Milian's fiancé, Jas Price, while there.
The pair posed for a photo together at the concert, which Jas jokingly captioned: "ThreeKings".
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