Another source told us the couple “Looked extremely in love” and were “Affectionate all night.”

“You could tell that Tristan is really in love with her and stuck by her side all night,” the insider dished.

“The family loves Tristan and they were all taking photos with him and really treated him like a family member.”

The family’s go-to florist, Jeff Leatham, was in charge of the stunning floral arrangements.

Even Kris and her bestie, Melanie Griffith, shared some social media posts after the fun night.

We’re told Khloe and Kourtney stayed until around 2:45 a.m., while everyone else left at about 1 a.m. Khloe’s surprise party comes just a few months after she threw Tristan his own gold-themed surprise party in March for his 26th birthday.

On Saturday, Kim and Kourtney threw daughters North West and Penelope Disick a Moana and Hawaii-themed backyard birthday party.

North turned 4 earlier this month, while Penelope turns 5 in July..

Khloe Kardashian