"Real Housewives of Orange County" star Vicki Gunvalson's daughter and son-in-law are missing… missing a lot of weight, that is!

The reality TV star shared a picture of her daughter Briana and her husband Ryan Culberson on Instagram while gushing about their weight loss via the keto diet.
"Just wanted to share this incredible photo of Briana and @ryan_culberson," Vicki wrote. "Together they have lost over 85 lbs since last summer. She feels better and is healthier than she has been in a long time. Missing her so much across the miles, but couldn't be more proud of both of them."
Ryan also shared that same image, noting they've actually lost 86 pounds. He asks his followers, "What are you waiting for?"
Last May, Ryan told his followers that he and Briana were seriously interested in educating themselves on keto, and shared a photo of their meal a few days later, indicating that they were going to adhere to a strict keto diet, which is basically a low-carb, high-fat program.
In January, Briana shared a side-by-side image of herself that showed her face noticeably thinner.
"The face on the left is of an average American diet, never felt good, having constant lupus flares, and on and off steroids for almost a year," she wrote on her husband's Instagram page. "The face on the right is strict Keto, steroid free, and lupus flare free! I've lost 45 lbs on keto so far but most importantly my health has greatly improved!"
Briana is one of many people in the public eye who have praised keto, including Al Roker Mark Consuelos and "Jersey Shore" star Vinny Guadagnino. The diet has been criticized by others in the health field.