But Braxton, who is divorcing Herbert, deleted the post after several hours, as E! Online reported.
"Vincent Herbert is having a baby," Braxton, 40, reportedly wrote, adding that a woman "decided to let me know about it tonight!!"
Braxton, who starred on the reality show Tamar and Vince with her husband, noted in the wild Instagram post that the woman "should check public records on Christmas" and that Herbert "called back" despite a "protection order," "begging and lying."
"Smh happy new year folks!! Ladies and gentlemen know that 2018 is a FRESH start and if i can leave this liar u can leave yours too," Braxton continued.
Songwriter and music producer Herbert has not commented on what Braxton wrote about him.
As Radar readers know, Braxton filed for divorce two months ago to end her nine-year marriage to Herbert. He is the father of her son Logan, 4.
According to bombshell court divorce docs, Braxton sought to avoid paying spousal support to Herbert and wanted full custody of their boy.
According to the docs, Braxton asked for "all assets acquired prior to date of marriage and during marriage by gift, inheritance, devise or descent."
The two were married in 2008 and have made headlines ever since for their tumultuous relationship.
It's not the first time Braxton has turned to social media to share her feelings about Herbert. She recently hit Instagram to write that together they were only hurting their family and making each other miserable. Braxton said she had been living a lie with their marriage.
"I told myself I would do whatever it took to keep my family together… hoping we could offer them hope, faith, Love & dignity that I once possessed. But the truth is all of those things are NOT within the marriage of Tamar & Vince… at least not anymore," she explained to fans.
Their lives have been full of bizarre incidents. For example, Herbert was involved in a bad car accident earlier this year.
Although Braxton shamed Herbert online on Dec. 30, in the past, she has said, "I will always love him, and what will be, will be."
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