Alongside a carousel of images featuring G Flip and herself, Stause, 41, wrote in the caption, "It is already Sept 22nd right now in Australia so HAPPY BIRTHDAY G!!!!🥰🥳"
"Imagine you took all of the things you love about an emotionally intelligent secure man, and all the things you love about a strong loving caring woman, and blended them together to make one magical human," she continued. "Oh and it would be cool if they could also be a sexy musical genius that is hilarious and maybe give them a hot Australian accent too because why not.🤯"
The reality star noted that "The universe had EXTRA TIME the day you were born and that deserves one hell of a celebration because wow-WELL DONE!! 👏👏"
As she concluded the post, she said, "Even though I could list a million things I love about you, your kind genuine heart is my absolute favorite."
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"I feel extremely lucky to be able to celebrate you constantly but especially today," she added. "Happy Birthday my love🥳Countdown is on for us to be reunited in the same time zone❤️🔥 @gflip."
In response to her sweet gesture, G Flip wrote in the comment section of the post, "BABYYYY!!! Thank you! This is so cute arhhhhh 🥺🥺🥺🥺 I adore and love every inch of you darling ❤️"
The post includes a photo of the pair hanging out in what appeared to be a recording studio, showing G Flip playing guitar while Stause sat and watched. Other photos feature a selfie of the two walking hand in hand and a snapshot of the couple having fun on the swings at a playground.
Stause and G Flip went public with their romance during the Selling Sunset season 5 reunion after moderator Tan France asked if she was seeing anyone special five months after splitting with costar and boss Jason Oppenheim.
"It's when they have the key to your heart, but the walls are down and there are no rules or regulations, just love and support," Stause explained at the time. "Plus, it ties into real estate, which is actually quite cute!"
Stause also revealed that her "favorite part" of their relationship "is just being around G."
"It's such a mood-lifting experience; if you ever had the pleasure of being in the same room with them, you would quickly see what I mean," she added. "I love feeling that endless support of just wanting the other person to be fully who they are."