Kourtney Kardashian and Scott Disick are reportedly "understandably miserable" after a male model filed for joint custody for their son Mason.

The couple went to dinner at Mr. Chow in Malibu on Saturday, two days after Michael Girgenti filed paperwork seeking joint custody of their 3-year-old son.

MailOnline published photos of the Keeping Up With The Kardashians stars walking apart from each other and not smiling. The report suggests that their serious demeanor may have been due to Girgenti's filing. It may have affected the couple's relationship and possibly led to them having heated discussions over Girgenti's paternity claims.

It is the second time the couple were seen in public since the filing at a Los Angeles County Superior Court on Aug. 8. Mail Online's report also shows photos of the reality stars leaving a lawyer's office.

A source told Radar Online that the model's claims are false. An insider said Kardashian "did not have sex with that model."

"This whole thing is so ridiculous," the source close to mother-of-two said. "She thinks it is stupid and it really isn't true. Kourtney knows who the father of her son is and it isn't this guy," added the insider.

According to TMZ, Gigenti filed the paperwork in a bid to get Kardashian have the child take a DNA test because he is questioning the boy's paternity. In the suit, obtained by the TMZ, Girgenti wrote he had an alleged sexual encounter with the reality star. He said they had "unprotected vaginal sex" and that he "ejaculated inside [Kourtney's] vagina" in his Glendale home.

Enstars reported in March that Girgenti denied Kardashian's long-term boyfriend, Scott Disik, is the biological father. Disick is also father to her daughter Penelope, 13 months. The male model claimed he slept with Kardashian in March 2009 - nine months before she gave birth to Mason on Dec. 14, 2009.

Girgenti told InTouch Weekly that he and the Kourtney & Kim Take Miami star became physical on their third date at his Glendale, Calif. apartment. Girgenti described their sexual encounter in detail in the bombshell claim. He said they met after they posed alongside each other in a photo shoot for 944 magazine in August 2008.

Tags
Kourtney kardashian, Scott disick, Keeping Up With The Kardashians 8