While everybody's been buzzing about Kylie Jenner being pregnant, few have noticed that her older sister Khloe Kardashian has also revealed that she is expecting her first child. And with Kim's surrogate also carrying a Kardashian, it seems Christmas 2018 is going to be a huge family affair.

Khloe Kardashian at House of CB flagship store openingKhloe Kardashian at House of CB flagship store opening

It seems pregnancy is contagious in the Kardashian household. 33-year-old Khloe has been dating basketball player Tristan Thompson for a little over a year now, and now they've confirmed that they are expecting their first child together. 

The 'Keeping Up With The Kardashians' star had been making subtle hints about her status on Snapchat, but now sources have confirmed the happy situation to various media publications. 'Yes, Khloe and Tristan are expecting and they are absolutely thrilled', an insider told People. 'This isn't something they were in a rush to announce to the whole world, and it's only been in just the past week or so that they've felt comfortable telling most of their inner circle.'

It's an extra special moment for Khloe given that she was previously told by doctors that she may struggle with fertility problems; something that deeply shocked her as she had been visiting the clinic in the hopes of becoming a surrogate to Kim's next baby. Needless to say, she and Tristan immediately started planning for a family.

'Tristan and I definitely talk about starting a family. He wants to have about five or six kids with me and that's lovely', she said on the 10th anniversary special of KUWTK. 'We could start at one and we could grow from there. But now knowing I'm not on birth control is scary. It's like a really big step.' 26-year-old Tristan is already a father to his ex-girlfriend Jordan Craig's baby Prince Oliver, who was born in December 2016.

Sources suggest that she's around four months pregnant, which means that she and her 20-year-old sister Kylie Jenner will be due at around the same time. Only days ago was it revealed that the latter and her boyfriend Travis Scott were expecting, but it looks like the whole family is thrilled.

'Things were complicated a bit by Kylie's announcement as they don't want to be seen as intruding on that moment for her but it is now reaching a point where Khloe doesn't want to be openly lying to people, and just staying quiet isn't going to work anymore', a source told People about Khloe's announcement.

More: Kylie Jenner is pregnant

Of course, Kylie had already stolen the spotlight from Kim Kardashian and Kanye West, who's third child is due in January and will be born via surrogate.