“Selling Sunset” Stars Mary Fitzgerald Bonnet and Jason Oppenheim Announce Their Dog Niko Died

"If love could have saved you, you would have lived forever," the celebrity realtors shared in a touching tribute

Selling Sunset stars Jason Oppenheim and Mary Fitzgerald Bonnet are mourning their dog Niko.

On Thursday, the former couple shared that their older dog, Niko, died at 18 years old. The two previously dated and shared custody of their two dogs, Niko and Zelda, after their split.

The celebrity realtors penned a heartfelt tribute to their dog in a shared Instagram post that featured multiple photos of Niko, Oppenheim, 46, and Fitzgerald Bonnet, 43, throughout the years.

The pair began the post by sharing how Niko made them “smile and laugh, and filled [their] world with immeasurable happiness,” for the past 18 years. “With your unconditional love and loyalty, you comforted us when we cried and helped heal our hearts when they were broken.”

The Instagram carousel included photos of Niko throughout the years, with older photos of the dog as a puppy with his owners.

Along with older photos of Niko, the tribute post also included images of Oppenheim and Fitzgerald Bonnet posing for professional photos with Niko, and their other dog, Zelda, as well as Thor, the dog Fitzgerald Bonnet shares with her husband Romain Bonnet.

The post also included a photo of Fitzgerald Bonnet and Bonnet with the three dogs. Along with memorializing their dog in the post, Fitzgerald Bonnet and Oppenheim shared a photo of matching tattoos of Niko’s name on their forearms. Oppenheim's also included a small paw print.

Related: Jason Oppenheim's Dating History: From Chrishell Stause to Marie-Lou Nurk

The post continued to share how Niko taught the former couple and their friends and family “valuable lessons.”

“You opened our eyes to depths we had no idea love can reach, taught us a higher level of patience and selflessness, and showed us what true loyalty and devotion looks like,” read the caption. “Even at the very end when your body and mind were failing and beyond exhausted, you still tirelessly struggled to hold on for us, refusing to give in.”

The two confessed how difficult it was to say goodbye to Niko, explaining that it was their “turn to be selfless, and strong” for Niko. “Tearing our own hearts out so we could help you to avoid suffering was the only loving option we had. It was the hardest thing we have ever done.”

“If love could have saved you, you would have lived forever. We miss you so much already, but you’re at peace now. We know you are still with us, just in a different form,” continued the caption.

Related: 'Selling Sunset' Star Mary Fitzgerald Says Reality TV Is 'Not My Cup of Tea': It 'Makes Me Uneasy'

The TV personalities admitted how they “struggle to find the words to describe” their feelings for him, adding “because nothing can express the love and joy that fill our hearts, where you will always remain.”

“You have changed our lives forever. Until we make it to where you are, we are sending you all of our love, you are forever and always our baby boy. Our bubby, Our Niko,” concluded Oppenheim and Fitzgerald Bonnet.

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