Heather Dubrow is sharing her love for her daughter Kat as she celebrates her 16th birthday.
On Wednesday, the Real Housewives of Orange County star, 53, paid tribute to Kat with a sweet post on Instagram, sharing a set of throwback photos of her daughter as a little girl.
In the snaps, Kat drinks juice from a champagne glass while sitting in a high chair. Another photo shows Dubrow toasting with the toddler as they smile for the picture.
"HAPPY BIRTHDAY KATTY!!!! Cheers to the cutest, best, funniest,sweetest, smartest 16 year old !!!! I love you so much and I'm so Proud to be your Mommy !!!! ❤️❤️❤️," Dubrow captioned the post.
Along with Kat, the reality star and husband Terry share daughters Max, 18, and Coco, 11, plus son Nick, 18.
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Speaking with PEOPLE in February, Dubrow shared that, one year after her eldest daughter Max came out as bi, her second daughter Kat came out as lesbian.
"We've got four kids, they are different genders, different sexualities, and all at interesting places in their lives, figuring out who they are and where they belong as humans," said the Bravo star.
A desire to share their family's story — and use their platform for good — factored into their decision to return to Real Housewives of Orange County last season. "I felt like our purpose is to keep those conversations going in other families," said Dubrow.
Added her husband Terry, renowned plastic surgeon and the star of Botched, "Coming out with your sexuality is something that broadly affects a lot of different people. We just want people to realize it should be part of normal conversations."
The kids themselves said the live-and-let-live vibe in their home has made a huge difference in feeling at ease as they explore their identities.
"She's asked me trillions of questions that really show she cares," said Kat at the time. "She's asked me about my pronouns. It's really easy to talk to her. It's not like I have to build up courage if I have something to tell her."