Kourtney Kardashian arrives at the 2014 Elton John AIDS Foundation Oscar Party in West Hollywood
IN PHOTO: Television personality Kourtney Kardashian arrives at the 2014 Elton John AIDS Foundation Oscar Party in West Hollywood, California March 2, 2014. REUTERS/Gus Ruelas REUTERS/Gus Ruelas

The members of the Kardashian Jenner clan have been celebrating birthdays left and right since late October. This time around, it's little Mason Disick's turn to celebrate. The adorable little man doesn't officially turn 5 until Dec. 15, but it seems like the family decided to celebrate a couple of weeks early. It was just as well since the party had a spooky Halloween theme inspired by "The Nightmare Before Christmas."

The birthday spookfest involved lots of makeup and scary costumes. Mason's aunt Khloe Kardashian, or "Koko" as the kids like to call her, dressed up as Sally Skellington from the film. She was in full-on Sally makeup and costume and revealed that her sister Kourtney made her believe that everyone was going to go all out with the costumes as well. In a photo she posted of herself with her sister Kylie, who seemed to be dressed casually, she said: "Kourtney pulled a "mean girl" move on me and had me dress like Sally from The Nightmare Before Christmas while everyone else was mad chill. lol thanks@kourtneykardash #MasonsBirthdayBash"

Khloe also posted another photo of herself complete with red hair and Sally makeup alongside Kendall Jenner, who at least was made up to look like a character from the film as well. The makeup work for the occasion was done courtesy of family friend and makeup artist Joyce Bonelli who was also in attendance with her own kid. She didn't only get all the adults dolled up for the occasion but the kids were fully made up as well. Both Mason and Penelope Disick sported bony Jack Skellington faces along with her own son.

Kendall posted a photo collage of all the fun activities during the party, saying that Mason throws the best parties complete with a scary-go-round. Kourtney and Mason have both taken a massive likig to the film and it's characters. They had posed for a photo with Jack and Sally Skellington while on a trip to Disneyland to visit the Haunted Mansion ahead of Halloween.

Kourtney also shared a photo of the decorations at the front of the house where a giant Jack Skellington stood beside a Christmas tree, which seems to be confused between Halloween and Christmas. Kourtney is due to give birth in the next couple of weeks which might be the reason behind the early birthday bash. Meanwhile, "Keeping Up With the Kardashians" season 10 is currently in production.