"There was talk about whether it should be Tatum Robert or should it be Robert Tatum," the source shared to the publication.
"Some in the family were leaning more towards Robert, because it honours her dad and her brother."
The source also added that Khloe's choice of name was a while in the making.
"It took Khloe a little while to settle on the name but ultimately she went with Tatum Robert, which is in keeping with Tristan and True's names starting with a T."
"Khloe wanted a name that was kind of unusual but not too out there and also keeping with the T theme."
Last year, Khloé has revealed that she wanted to take her time naming baby number two, but that hasn't stopped fans guessing.
Here were all the fan theories surrounding Khloe's second baby (spoiler alert - they were kind of right!)
Reminder, True's name, while unique, was actually Khloe's grandmother's suggestion and it holds significance in Kris' family.
"I knew I wanted my baby to have a 'T' initial, so one night while we were all at dinner, thinking of some names, my grandma MJ suggested True," Khloé wrote when True was born.
"She told me it was my great-grandfather's first name and my grandfather's middle name."
Fans believed it was likely Khloé would follow a similar formula for her son. Rumours began swirling that his middle name will be 'Robert' after Khloé's father's first name, or George which was Robert's middle name.
Prior to True's birth in 2018, Khloé told Ellen DeGeneres that the baby would be called Tristan Junior if it was a boy. However, fans believed it was unlikely that Khloé would go with that following the year's dramatic events.
Although Tristan and Khloé are co-parenting both kids, the news around their second child was marred with multiple cheating allegations.
Some fans speculated that Khloé would choose something in the same vein as True, an ideal such as 'Loyalty' or 'Honest,' whilst others think she'll continue using her family as inspiration.
Khloé's paternal great-grandfather was named Tatos, which he changed to Thomas when we emigrated to America.
Tatos fits Khloé's naming conventions well. It's a family name, it's unusual without being truly out-there and it starts with 'T'.
The first episode of The Kardashians season two gave fans a number of clues surrounding the name of Khloé's bub.
During the debut episode, Khloé confirmed her baby's name would start with a T.
Tyler, Tucker, Taytum and even Travis were all suggested by Kris!
Kris' partner Corey suggested Ten at the baby shower - whilst others suggested Tritan, Teo and Tiger.
Related: Everything we learnt about Tristan, Khloé and baby no.2 in the debut episode of The Kardashians season two.
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