Rob Kardashian lashed out at Blac Chyna in another round of their nasty lawsuit battle but his “erratic” behavior was no surprise to his estranged baby mama, Breaking Celebrity News exclusively learned.

“Rob has been manic lately,” a source close to Kris Jenner’s only son told Breaking Celebrity News. He skipped his mother’s Christmas Eve party and was hiding in his house over the holidays.

Kardashian, 30, filed another round of vicious court documents against Chyna, 29, and the insider told Breaking Celebrity News that his relationship with his baby mama had deteriorated.

“Rob has been so erratic in his communication with Chyna lately,” the source snitched. “He vacillates from normal conversations about drop-off for Dream to begging Chyna to see him and then calling her a bad mom. He seems unstable.”

The warring couple were fighting over their canceled reality show, with Chyna claiming Kardashian’s “became media predators, [expletive]-shaming” her when they killed the show after it had already begun filming a second season.

“Chyna was blindsided by these new court documents,” the insider told Breaking Celebrity News. “But she sees the crazy way Rob is acting lately and nothing surprises her.”

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