According to sources, the former couple's son, Tatum Thompson, who was born at the end of last summer, was initially legally a Kardashian. He also reportedly was not given the name Tatum at first, but it remains unclear what the first name was that Kardashian chose for her newborn.
Eventually, The Kardashians star dropped the Kardashian name for her little boy, allowing Tatum to legally be named after her cheating ex-boyfriend.
Kardashian's decision to first give Tatum her last name likely had something to do with Thompson's latest cheating scandal, which resulted in the birth of a little boy with Instagram model Maralee Nichols.
Thompson and Nichols conceived their child while the NBA pro was still dating the reality star. And despite knowing Nichols was expecting his baby — as she filed a paternity suit in June 2021 — Thompson encouraged Kardashian to speed along their own fertility journey while keeping her in the dark about the situation.
In November 2021, the then-couple conceived their second child via surrogate. Mere weeks later, it was revealed that Thompson had been unfaithful, yet again, to the mother-of-two.
After demanding that a paternity test be done for Nichols' baby, Thompson confirmed in January 2022 that he was the father while apologizing to Kardashian for all he's put her through.
Kardashian and Thompson — who are also parents to True Thompson, 5 — have managed to keep their second child's identity hidden for almost a year, keeping his name a mystery and only offering glimpses of the back of his head on social media.
Never miss a story — sign up for the OK! newsletter to stay up-to-date on the best of what OK! has to offer. It’s gossip too good to wait for!
However, on the Thursday, May 25, Season 3 premiere of The Kardashians, she finally revealed his moniker, saying during a confessional with a sigh: "Naming a human is really hard."
Despite going their separate ways before welcoming their second bundle of joy, the on-again, off-again exes have maintained a healthy co-parenting relationship. The famous pair was most recently seen attending True's pre-school graduation on Wednesday, June 7, where they were joined by Kylie Jenner and her ex Travis Scott — who were also celebrating their 5-year-old daughter Stormi's big day.
TMZ reported that Tatum initially had his mom's last name.