Rob was accused of faking the relationship to make money from their TV show.
On Instagram Rob posted a sweet snap of Chyna and wrote: ‘Love this woman can't wait for my baby girl to come already.’
It comes after InTouch Weekly accused Rob and Chyna of ‘faking’ their relationship to get a $2 million payday from their E! reality show.
"Rob had agreed to have a fake relationship with Chyna because his momager, Kris Jenner, got E! to pay him over $2 million to do a show," a source told the magazine.
The source added that Rob now "completely regrets" his decision and is currently turning down any media opportunities that would otherwise help promote the series.
However Rob is said to be unwilling to come clean about the "staged" relationship.
"It would be too humiliating. The lie has gotten so out of control, there's no turning back,” the source added.
But on this Sunday’s episode of 'Rob and Chyna' the dad-to-be gets some very good news, as he’s told he’s free of diabetes.
In a preview clip for the episode Rob is seen telling Chyna: “He just told me all my numbers, and I’m completely free of diabetes. That’s like, the best news I’ve heard all year, literally.”