Rob Kardashian felt "neglected" by fiancee Blac Chyna.
The celebrity couple - who are currently expecting their first child as well as filming a reality TV show together - recently had a huge fight that led to Rob deleting all traces of his fiancé from his social media.
Although they have now made up, insiders claim Rob was struggling to cope with Chyna - who has a three-year-old son, King Cairo, with ex-boyfriend Tyga - having so many other commitments in her life.
A source told Us Weekly magazine: "Everything with Chyna is moving so fast. ... She's a single parent and filming the show and all of her other work commitments, so Rob has been feeling neglected by her. She has also been doing things on her own a lot with her girlfriends."
Rob, 29, only started dating 28-year-old Chyna in January, before getting engaged in April, and insiders also believe the fast pace of their relationship caused their huge bust-up.
One source added: "Yes, it was a fight, but they will be over it and basically are. They've been spending a ton of time together and filming a show together. Add to that the stress of a new relationship and it's inevitable that there will be some tension and fighting. It was an explosive fight."
Friends say they are now "back in love" and looking forward to the arrival of their baby, which is rumoured to be a little girl.
Their reality TV show 'Rob & Chyna' is set to air on E! next month.
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