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Britney Spears' cousin Alli Sims has been ordered to testify in the singer's custody battle with her ex-husband Kevin Federline.
Alli, who until recently worked as Britney's assistant, was served the legal papers after partying with the star in the Hollywood Hills yesterday.
A source told People magazine: "Alli was really shocked and covered her face. She was really distraught and said 'Oh my God.' "
The subpoena papers, sent by Britney's ex-husband Kevin Federline, will force Alli to testify about the star's parenting skills.
Alli recently defended the Toxic singer when she insisted she is a great mother to 22-month-old Sean Preston and Jayden James, 10 months.
She said: "She's a wonderful mom and she is so hands-on. Britney loves those babies to death. And they adore her."
Last Wednesday, Kevin filed for primary custody of his two children with Britney.
The 29-year-old is hoping he will be awarded primary physical custody because of Britney's recent erratic behaviour.
Kevin and Britney, whose divorce was finalised last month, originally agreed to equally share custody of their sons.
Meanwhile, Kevin Federline was humiliated when he turned up to "star" in a new film only to discover he had been fired.
Kevin arrived for on the set of The Night Watchman, which stars Keanu Reeves, after his manager forgot to tell him makers Fox Searchlight had dispensed with his services.
A source claimed: "He only had a very small role. However, he was fired from the film and his manager didn't tell him. Kevin found out when he turned up for a wardrobe call."
Reports previously suggested Kevin would be "starring opposite" Keanu in the The Night Watchman, but Fox Searchlight insist they never even cast him in the first place.
Kevin's manager refused to comment on the mix-up.
The 29-year-old's acting experience extends to appearing briefly in an episode of hit US TV show CSI: Crime Scene Investigation last year, and a small role as a dancer in 2004 film You Got Served.
Kevin will now have more time to concentrate on fighting ex-wife Britney Spears for custody of their children.
- BANG! SHOWBIZ