Blac Chyna's mum urges Rob Kardashian to do right by her daughter

Blac Chyna's mum is pleading with her fiance Rob Kardashian to fix their relationship before he loses her.

On Sunday's episode of their reality show, Rob & Chyna, Chyna asked her fiance to accompany her on a trip back to her hometown of Washington, D.C. for America's Fourth of July holiday weekend - and meet her mother, Tokyo Toni.

"This D.C. trip means so much to me and if Rob doesn't go this could be a make or break in our relationship," she said on the show.

"We are going to D.C. and being around people I don't know and out of my comfort zone," he said. "But my relationship with Chyna means everything to me so I am willing to do this."

During the episode, the 28-year-old, who is expecting Rob's daughter, showed her fiance her childhood home and the strip club she worked at before graduating college. The 29-year-old and Chyna, who also has three-year-old son King with rapper Tyga - the boyfriend of Rob's sister Kylie Jenner, then headed to a family barbecue at Toni's house, when the worried mum quizzed her daughter and Kardashian about their wedding plans.

"When (are) you going to get married?" she asked the pair.

The couple explained it had some issues to work out before heading down the aisle, but Toni urged the reality star to get himself together so he can be a good husband to her daughter and a great father to their child.

"You gotta stop what you're doing," she tearfully said. "(Chyna) don't need a baby, she needs (you to be) a father... You can't do what you're doing. You're going to ruin it."