Khloe Kardashian’s Son Tatum Initially Had Her Last Name Before She Changed It to Thompson

Making a change. Khloé Kardashian's son, Tatum, shared her last name when he was born, but she reportedly changed it to Thompson sometime after his arrival.

The Good American founder, 38, reportedly used the name "Baby Kardashian" on Tatum's birth certificate after his arrival in July 2022, according to multiple reports. When she decided on a name, the reality star legally changed the little one's moniker so that she shares the same last name as his dad, Tristan Thompson. Entertainment Tonight noted that Tatum's name was automatically made "Kardashian" after his birth because the Hulu personality and the NBA player, 32, are not married. The Keeping Up With the Kardashians alum and the Los Angeles Lakers forward — who also share daughter True, 5 — dated off and on from 2016 to 2021.

The Strong Looks Better Naked author kept her son's first name a secret for the better part of a year, finally making the announcement during the season 3 premiere of The Kardashians in May. “Naming a human is really hard,” she joked during the episode, which was filmed last year.

One month prior, Kardashian explained why she delayed sharing the baby's name for so long after his arrival.

“At first, I really did not know what I was going to name him,” the California native explained during an April appearance on The Jennifer Hudson Show. “I wanted to meet him and feel him out a little bit. And so, 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, so now, if my daughter outs me, I’m screwed.”

Us Weekly confirmed in July 2022 that Kardashian and Thompson were expecting their second child together. When the baby was conceived in late 2021, the duo had secretly reconciled, but they split again after Thompson welcomed a son with Maralee Nichols. In a paternity lawsuit, the fitness pro claimed that she and the Canada native had been intimate while the athlete was still dating Kardashian.

Thompson and Nichols' child, Theo, now 18 months, arrived in December 2021. The former Cleveland Cavaliers player also shares son Prince, 6, with ex Jordan Craig.

During season 1 of The Kardashians, the Kocktails With Khloé alum revealed that she found out about Thompson and Nichols' relationship when the news was made public.

“I find out what Tristan is doing with the rest of the world. A courtesy would be not doing it," the former Revenge Body host said in a June 2022 episode. "But fine, if you do it, you are not even going to give me a f–king heads-up before the rest of the world? It is just an additional slap in my face. It is humiliating. I am embarrassed."

Since Thompson signed with the Lakers in April, rumors have swirled that he and Kardashian plan to rekindle their romance, but an insider recently told Us that a reconciliation is unlikely.

Sign up for Us Weekly's free, daily newsletter and never miss breaking news or exclusive stories about your favorite celebrities, TV shows and more!

“Khloé has no idea what it would take to ever get back together with Tristan, but she really can’t imagine that ever happening,” the source said last month. “She’s grateful they have a strong and healthy coparenting relationship and that’s all she could ever hope for. As long as Tristan continues being there for his kids, she’ll continue to encourage her loved ones to show their support for him.”