It’s time to close the book on summer vacation. 

Which can only mean one thing: back to school. However, not all parents are ready for this new chapter. 

Take Khloe Kardashian, for instance, who admitted she couldn’t believe her daughter True Thompson was already starting first grade.

“It’s always such a rollercoaster of emotions when True starts a new school year,” the reality star—who shares the 6-year-old as well as 2-year-old son Tatum Thompson with ex Tristan Thompson—wrote on Snapchat Aug. 26. “This year is a big milestone for her… first grade. I’m not going to lie, I am having a really hard time processing the fact that she’s going into first grade.” 

And while Khloe is certainly proud of True, she noted she also felt “this strange mixture of loss, anxiety and fear.” 

“There’s this undeniable feeling that I’m losing parts of who she was with each day that passes,” the Good American mogul continued. “The little parts of who she used to be are being replaced with new parts that will make up the next little amazing person she will become. And I miss her. All the little versions of her who I used to know. Time moves fast, faster every year it feels like, and this new school year is a reminder to me to fully embrace every moment and soak it all in.”

After all, Khloe—who celebrated her eldest’s first day with a balloon and crayon display—expressed how True “is more than I could ever have dreamed of in a daughter” and “seeing her grow makes me excited for the years and experiences ahead.”

Sarah Michelle Gellar could relate to what KoKo was going through as her and husband Freddie Prinze Jr.'s daughter Charlotte, 14, and son Rocky, 11 also experienced big milestones: beginning high school and middle school.

Posting a video of herself dancing as her kids headed back to class, the actress wrote on Instagram, “Parents …. Who gets me today?!? But also…. How do I have a high schooler and a middle schooler?!? Time is a b---h.”

As the back-to-school season continues, keep reading to see more celebrity parents who’ve shared photos of their kids’ first day.

She's got the right stuff! The Lizzie McGuire alum and Matthew Koma's oldest daughter Banks started kindergarten. 

"My queen. My boss. My CEO. My top dog. My big cheese. My kindergartener," Hilary wrote on Instagram Aug. 29. "Let’s go baby girl!!!"

The Euphoria actress said it was "surreal" to be starting her final year at University of Southern California in Los Angeles.

Time flies when you're keeping up with the Kardashians! Case in point: The reality star was having "a really hard time processing the fact" that her daughter True Thompson—who she shares with ex Tristan Thompson—was heading into the first grade. 

"There’s this undeniable feeling that I’m losing parts of who she was with each day that passes," Khloe wrote on Snapchat Aug. 26. “Time moves fast, faster every year it feels like, and this new school year is a reminder to me to fully embrace every moment and soak it all in.”

The country singer and her husband Eric Decker's three older kids—Vivianne, Eric II and Forrest—returned to school on Aug. 19. 

And with baby Denver at home, Jessie wrote on Instagram, "I still can’t believe I have a middle schooler and a 6month old."

Back to school season was off to a shining start for the comedian and Brittany Bell's son Golden Sagon, who started the fourth grade at just 7 years old after skipping kindergarten and pre-K.

Meanwhile, Golden's sister Powerful Queen—who Nick also shares with Brittany—began pre-kindergarten.

As the Good Night, Sister author and her husband Chris Pratt prepare to welcome baby No. 3 together, their daughters Lyla and Eloise headed off to their first day of class.

Katherine captioned this Aug. 18 photo of the girls wearing their custom Stoney Clover backpacks, "How is it already back to school time?!"

Britney Spears' nieces are growing up fast! Maddie—who Jamie Lynn shares with ex Casey Aldridge—began her junior year of high school.

Meanwhile, Ivey—who the Zoey 101 alum shares with husband Jamie Watson—became a first grader.

There's never a right time to say goodbye. That was probably what the "Run It!" singer and Nia Guzman were thinking when daughter Royalty went off to fifth grade on Aug. 27.

The Saved by the Bell alum sent kids Gia, Dominic and Santino off to school on Aug. 20, joking that means he and wife Courtney Lopez "have homework" to do.

"One (and only) year with all 3 kids at the same school," Courtney added in an Instagram post of her own. "So excited to wake up earlier, make lunches they won’t eat and do homework I can’t understand!"

The Teen Mom: The Next Chapter star embarked on not one, but two new chapters when her and ex Corey Simms' twins Aleeah and Aliannah started high school, and her youngest daughter Adalynn—who she shares with ex  Jeremy Calvert—entered middle school.

Backstreet's back to school! The former boybander posed with his and wife Lauren Kitt Carter's three kids Odin, Saoirse and Pearl, writing on Instagram Aug. 23, "Nothing better than watching your children grow and learn."

The HGTV host shared an emotional hug with her oldest son Drake—who she shares with husband Chip Gaines alongside their younger kids Ella, Duke, Emmie and Crew—as he headed back to Baylor University for his sophmore year.

The Buffy the Vampire Slayer alum showed off the back-to-school plaques she made for daughter Charlotte and son Rocky—both of whom she shares with husband Freddie Prinze Jr.—as they began high school and middle school, respectively.

Good luck, Mia! The actress—who played the titular toddler in Good Luck Charlie—started her sophomore year of high school on Aug. 19. 

She quipped on Instagram, "Cue the comments about feeling old."

Teenagers Braydon Wilkerson and Tucker Wilkerson—who the Sabrina the Teenage Witch actress shares with husband Mark Wilkerson—headed off to school on Aug. 7.

She got the boy to his class! The singer was on hand to watch her and ex Mike Caussin's son Jace start kindergarten on Aug. 9.

Meanwhile, the former couple's daughter Jolie began third grade.

The Bachelor Nation star's daughters Kinsley and Charlie started the seventh and fifth grade, respectively.

"I just can’t believe how grown up they are," she wrote on Instagram Aug. 22, "& that they still love to match…& that I still cry on the first day of school no matter how long I’ve been doing this."

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