The Keeping Up with the Kardashians star hit headlines in late September (17) amid rumours suggesting she was pregnant with her first child.
Khloe has remained quiet about the claims, but now multiple sources have told People.com the 33-year-old and her basketball player beau will be having a son early next year (18).
Tristan, who plays for the Cleveland Cavaliers, is already a father to a 10-month-old boy named Prince Oliver, conceived with his ex-girlfriend Jordan Craig not long before the 26-year-old began dating Khloe in September, 2016.
The gender news emerges a day after Khloe's mum Kris Jenner appeared to drop big hints about the pregnancy as she attended the Women's Wear Daily (WWD) Apparel & Retail CEO Summit in New York on Tuesday (24Oct17).
"I'm over the moon for her," she gushed to U.S. news show Entertainment Tonight about her third child's blossoming love life. "We love Tristan so much, and she's so happy, and she's been through so much.
"Just seeing her be able to do something so creative with (her denim line) Good American, that's her passion. On top of it, to be in such a great place in her personal life is amazing. She's really happy."
Khloe was previously married to another basketball player, Lamar Odom. They split in late 2013 after four years of marriage, but only finalised their divorce last year (16).
Khloe isn't the only member of the Kardashian/Jenner clan reportedly pregnant - her younger sister Kylie Jenner is said to be having a child with her rapper boyfriend Travis Scott, too. She has also failed to confirm or deny the baby speculation, which suggests she is due in February (18).
Meanwhile, older sister Kim Kardashian has confirmed she and husband Kanye West have a third child on the way via a surrogate mother. Their kid, a girl, is due in January (18).© Cover Media