The 20-year-old reality star has refused to be drawn on reports she's expecting her first child with partner Travis Scott - who she has been dating for five months - but a spokesperson for her father, who was previously known as Bruce, has spoken up to dismiss claims the former Olympian only learned the news online.
The representative told The Sun Online that Caitlyn had been told and added: ''All I can tell you is that it was some time ago.''
Kylie's mother, Kris Jenner, has refused to confirm the news.
The momager was texted by 'Keeping Up with the Kardashians' executive producer Ryan Seacrest and replied while he was on air hosting 'Live! With Kelly & Ryan' on Monday (25.09.17).
Ryan said: ''By the way, so, Kris says Kylie's not confirming anything. So, that's the news from the family this morning.''
And asked about the speculation over the weekend, Kris said: ''She's not confirmed anything. I think it's kind of wild that everyone is just assuming that that's just happening.''
It has been claimed Kylie's family are ''over the moon'' with the prospect of a new addition to the family.
A source said: ''The family is over the moon! Kylie loves how close knit her family is and is thrilled to bring that to her immediate family. Kylie feels more prepared than ever to be a mom.''
It comes after a source claimed Kylie had ''always wanted'' to be a young mother.
They shared: ''Kylie is doing well and is happy. Kylie always wanted to be a young mom. She may be young, but she's very maternal and has lots of practice with babies! She's a very hands-on aunt and was basically a step-mom to Tyga's kid. The baby will be very well cared for and so loved. Kylie is excited that her baby will have cousins close to her age too!''