Just when it seemed like things had become civil between Nas and Kelis, the two have run into more custody problems. According to an April 5 report from TMZ, the rapper has filed legal documents asking a judge to penalize Kelis after he says the singer refused to let him take their son during Passover, which started on March 30.

Nas says it was his weekend to have their 8-year-old child Knight, but Kelis claimed the child wanted to stay with her during Passover. The rapper also alleges that his ex-wife has made it difficult at times for him to get his son.

Nas claims he once arrived at Kelis' house to pick up Knight and the singer screamed at him, saying he couldn't take the child. The rapper also says Kelis has refused to allow him to pick up Knight from school.

In March, Nas and Kelis reached a joint custody agreement. While details of the agreement were not publicly disclosed, it's believed that it was very specific and laid out who would be taking Knight on various holidays throughout the year.

The agreement came just a day after it was reported that lawyers for the artists were hurling insults at each other. Kelis claimed that Nas' attorney referred to her legal representation as a "fattie" and "dick."

Nas is now seeking $22,000 for the attorney bills he has had to pay every time Kelis has allegedly violated their custody agreement.

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