TMZ reports that Patton's people called the cops from a Malibu park where she was supposed to hand the estranged exes' 6-year-old son to a court-appointed monitor so that Julian could have a visit with his dad.
A source close to Thicke tells Us Weekly that Patton, 41, was almost an hour late for the meeting and refused to give Julian to the monitor when she arrived.
Other sources tell TMZ that Thicke, 39, also apparently violated a restraining order that Patton had against him and was just feet away from the About Last Night actress, although the Thicke source insists that the singer remained in his car the whole time.
Julian reportedly decided that he didn't want to go with the "Blurred Lines" singer and asked his mom to call 911, a source close to Patton told TMZ. But by the time deputies arrived at the scene, Patton and her son had left.
"Here's what happens," the source close to Thicke tells Us. "Paula finally shows up and won't let Julian out of the car, she doesn't want to hand Julian over. The moderator is going between them and Robin is sitting in his car, doing as he's directed. And for some reason she called her housekeeper, and the housekeeper who was at the house, not at the park, mind you, calls the police and says Robin is violating his restraining order. And Robin never got out of his car. Paula then takes Julian and leaves."
"When the police showed up, she was gone," the source continues. "They went up to Robin and they said, 'Someone called saying you broke the restraining order' and he said, 'No, this is my designated spot to pick up my son. We have joint custody and we do this every week, I stay in the car.' He had a full conversation with the police and they didn't do anything. The saddest part about this is that was his only time to see Julian."
"Paula was not an hour late," a source close to the actress tells Us Weekly. "What happens is, when Paula goes to hand off Julian to Robin, she is supposed to hand him off to a monitor. Robin is not supposed to be there because of the court-ordered restraining order. So he showed up despite the court order, and then Julian said he didn't want to go with his dad as soon as he saw him, so that's why the hand-off didn't end up happening."
Reps for Thicke and Patton have not responded to requests for comment.
The episode is the latest in a line of dramatic incidents involving the couple, who divorced in 2015 after 10 years of marriage.
As Us Weekly previously reported, Thicke was being investigated last month by the Los Angeles County Department of Child and Family Services amid allegations of child abuse for spanking his son.
Patton was granted a temporary restraining order against the Grammy-nominated singer last month, as well as sole temporary custody of Julian, after court documents, obtained by Us Weekly, revealed that Patton accused Thicke of physically assaulting her, cheating on her multiple times and having a serious cocaine problem. A source close to Thicke denied the domestic abuse allegations to TMZ.
TMZ reported last month that Thicke's lawyer claimed Patton herself was also under investigation by DCFS for alleged emotional abuse of her son.
Police were called to Patton's home in mid-January after she had a confrontation with Thicke when he arrived for a visit with his son and, according to TMZ, Julian refused to go with him.
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