It happens so fast! Sister Wives star Christine Brown shared a back to school photo of two of her daughters on August 8, and fans had trouble believing just how grown up the girls look these days. “First day of school!!” Christine, 47, began the post’s caption. “WAY too soon for all of us. Go get the world, my beautiful daughters. #firstdayofschool #senior #junior #momlife #beautifuldaughters.”

The girls pictured are Christine’s daughters Gwendyln and Ysabel Brown. Gwen, 17, is a senior in high school and Ysabel, 16, is a junior, according to the signs they held up in the photo. Time really does fly, doesn’t it?

Sister Wives fans could hardly believe their eyes and took to the comments to express their disbelief that Christine’s daughters are back to school and almost all grown up. “WOW! Where has the time gone?!” one fan wrote. “Have a great school year, Brown girls!!!” Another follower wrote, “Wow your girls got so big since season 1! I feel like we watched them grow!” Someone else said, “So awesome. They have grown up so much since the show started. Good luck this year ladies.”

Christine and her husband, Kody Brown, share six children together; besides Gwen and Ysabel, they have daughters Aspyn Brown Thompson, Mykelti Brown Padron and Truely and one son — Paedon. Aspyn, 24, and Mykelti, 23, are both married and out of the house, but the rest of the kids are still young enough for these fun back to school photos.

Christine shares all sorts of updates about her kids on social media, and fans of the TLC show can’t get enough of it. In late May, she also shared a photo of the same daughters on the last day of the previous school year, and her followers made similar comments about the girls then. “Oh my goodness they are getting so big, man I feel old!” one person wrote. No kidding — how do you think their mom feels?

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