The American said she was "confident" of giving birth to a boy "but God blessed me with my previous True", in a message to social media followers.
Referring to her eight-year-old nephew, she wrote on Twitter: "I wanted a boy so badly because Mason and I are so close. I love our bond.
"I felt confident in having a boy but God blessed me with my precious True and now I wouldn't know what to do with a boy.
"True has made me sweeter and more gentle. God gives you what you need. My BFF [usually intended to mean 'best friends forever'] 4Life."
Along with her sisters Kim and Kourtney, Khloé shot to fame as a star of the hit TV series Keeping Up with the Kardashians - which debuted in 2007.
I wanted a boy so badly Because Mason and I are so close. I love our bond. I felt confident in having a boy but God blessed me with my precious True and now I wouldn't know what to do with a boy. True has made me sweeter and more gentle. God gives you what you need. My BFF 4Life
— Khloé (@khloekardashian) July 28, 2018
The 33-year-old previously expressed her anticipation of reading Bible stories to three month-old True.
She also described "waiting and wondering" before her "greatest dream" was realised when she learned of her pregnancy.
Posting on her Instagram account last December, she added: "God had a plan all along. He knew what He was doing."
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