Psalm West ain't 'fraid of no ghost.

After all, Kim Kardashian and Kanye West's son had a Ghostbusters-themed party for his 5th birthday May 11.

The Kardashians star spared no detail for the celebration, transforming her home into the slime-covered Ghostbusters Firehouse, complete with massive neon green balloons and barrels of toxic waste. A wall of proton packs was also ready for each child, who hopefully didn't cross the streams.

Of course, no birthday celebration could be complete without some tasty treats. Kim showcased a variety of Ghostbusters-inspired snacks, including slime-covered nachos, Stay Puft Marshmallow Man cupcakes and a show-stopping cake. The two-tier dessert was adorned with green slime and topped off with a Slimer busting out the top.  

Following the tour, Kim—who also shares North West, 10, Saint West, 8, and Chicago West, 6, with Kanye—posted a loving Instagram Story with Psalm at the party May 11, writing, "My baby is 5."

And the SKIMS founder couldn't help but reflect on her youngest's recent milestone with a sweet post alongside photos of Psalm over the years.

"My baby," Kim wrote on Instagram May 9. "My sweet, smart, silly, independent baby boy turns 5 years old today! I can't tell you how blessed I feel to be your mom! Your calm energy is much appreciated in our house hold lol. You prove you can be the hulk, spider man or an archeologist any day of the week."

"I've never met someone who sleeps more than you do and one day I will show you the entire photo album I've made of your sleeps," the 43-year-old continued, "I love you so much always and forever."

Meanwhile, Kris Jenner also shared a loving birthday tribute for her grandson with a carousel of photos.

"Thank you for being such a blessing in all of our lives my Psalmy and for putting a huge smile on my face every time we are together," she wrote on Instagram May 9. "The joy you bring and the happiness you give to all of us is such a beautiful gift."

Now, read on to see how the Kardashian-Jenners celebrated Psalm's big day.