Khloe Kardashian is keeping up with her son's new moniker.

The Kardashians star has legally changed the name of her and ex-boyfriend Tristan Thompson's baby boy.

While the 13-month-old was originally listed as Baby Kardashian on his birth certificate, a Los Angeles county judge has officially granted the change to Tatum Thompson, per legal documents obtained by People Aug. 31.

Khloe and Tristan, who also share daughter True, 5, welcomed their son in July 2022 via surrogate. However, the Good American founder kept his moniker under wraps until the season three premiere of the reality show which aired earlier this year. And as the season went on, Khloe gave fans an update on her baby boy's nickname—or lack there of.

"Tatum's good," Kris Jenner said to Khloe during the June 10 episode of The Kardashians. "We could call him Tate. Everybody's gonna call him Tate." 

However, that nickname didn't fly with Khloe, who swiftly responded to her mom, "No, never gonna happen."

But while Khloe kept Tatum's name quiet for several months, it wasn't just for the show's big reveal. After all, she had a tough time deciding on what to call him

"I wanted to meet him and feel him out a little bit," she explained on the Jennifer Hudson Show in April. "At first, he didn't have a name. Then, he's been named but I've been waiting for the premiere of our show and I didn't know it was going to be this far out."

After finding a name that fits, these days Khloe is focused on growing her bond with her son.

"With True, it took me a couple days to be like, 'OK, this is my daughter,' and I was super into it—but just days," Khloe recalled on the Hulu show. "But with him, it's taken me, like, months. I love him and I love kids, but I definitely still don't have that complete bond. But you know, so many say it takes time."

But it's safe to say the bond has grown deeper between the mother-son-duo, as Khloe proved in her moving tribute to Tatum on his first birthday July 28.

"I am a firm believer in that God gives you what you need and I needed you. God knew my heart needed you," she wrote on Instagram. "I needed your sweet and precious Smile. I needed your angelic spirit. I needed a love only you could give me. I needed my son."

She continued in part, "I am so proud to be your mommy. So proud of the love and laughter we have in our house. So proud of your beautiful, gentle, loving, infectious spirit. You light up every single room."

To see a complete look at Tatum's cutest pics, no need to head to Hidden Hills, just keep scrolling...

Kris Jenner pays tribute to her 12th grandchild on his first birthday, writing on Instagram that she is "honestly in awe of how you look exactly like uncle Rob. It's wild and I love it!!!!"

She continued, "I love you my amazing Tatum!!! I love you my sweet boy."

Kris Jenner, Khloe Kardashian and baby Tatum celebrate the holiday.

Kris Jenner cuddles her 12th grandchild.

Tristan appears with Tatum in what marks the first photo of the child that the basketball player shared on his Instagram. He posted the pic on his son's birthday in July 2023, writing, "Tatum!! Happy birthday my son! You are a reminder of what life represents to me. You have taught me every loss comes a lesson and you are my gift. You are my reminder of all of God's messages. You are the reason that I began my story."

He continued, "The mistakes along the way are lessons not failures. There is no expiration date to reinventing yourself. Tatum your sweet soul reminds me of God's grace. You are a future king my son and I am so blessed to be your DaDa!"

Her flashed a perfect smile at the camera in this photo shared on his first birthday.

True proudly showed off her little brother in the kitchen.

The pair snapped an adorable selfie while enjoying some time outside.

Kim shared a glimpse with Tatum for his first birthday. "OMGGGG you are such a smoosh, the happiest baby boy of all time," she wrote July 28. "I can't even tell you how loved you are and how special you are!"

Kim also joked in her caption, "You are Rob's twin! LOL Your auntie loves you SO MUCH."

Tatum looked so grown up while rocking blue swim shorts and a straw hat.

On Tatum's first birthday, Khloe shared a throwback photo of her youngest wrapped in a towel.

Khloe's baby boy was dressed to impress in a firefighter hat.

Tatum wanted to investigate the foam during his big sister's bath time.

Tristan went to give Tatum a kiss in the series of images Khloe posted in her birthday tribute to the NBA star in March.

In a May 19 Instagram post, Khloe shared pics holding Tatum, who's facing away from the camera donning a grey t-shirt and a head of thick dark hair.

Khloe posted photos of True and Tatum bonding on a balcony, with True holding her baby brother as he grabbed onto the railing im one snap.

 

Tatum enjoyed some fresh watermelon while celebrating his first Fourth of July.

Khloe shared a selfie she snapped with Tatum and True at their cousin Psalm West's fire truck-themed fourth birthday party on May 7.

In the photo, the tot wears a red, plastic firefighter's cap and sits on his mom's lap.

 

Ahead of Tatum's first birthday, Khloe celebrated a major milestone when she shared a clip of her son crawling on her Instagram Story.

Khloe Kardashian shared a photo of Tatum Thompson's face for the first time while wishing "best father" Tristan Thompson a happy birthday in March.

The picture showed Tristan with his arms around his and Khloe's daughter True and Tristan's son Prince, who he shares with ex Jordan Craig.

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