The lines are getting more and more blurred in the bizarre legal battle between Robin Thicke, Pharrell Williams, and T.I. and the children of the late Marvin Gaye.

Now Gaye's kids Nona and Frankie are accusing the trio behind the hit "Blurred Lines" of playing dirty games, Breaking Celebrity News has exclusively learned.

In August 2013, Thicke, Williams, and T.I. (known by his real name, Clifford Harris, Jr.) filed a preemptive lawsuit over their song after Marvin Gaye’s estate and Bridgeport music reportedly threatened action against Thicke and his co-creators because “Blurred Lines” is too similar to Gaye’s “Got to Give It Up” (and also Funkadelic’s “Sexy Ways”).

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Thicke’s camp asked the court to rule that "Blurred Lines" was an original work.

In the lawsuit, Gaye's family was accused of making an invalid copyright claim since only expressions, not individual ideas, can be protected.  Williams has called the two songs "completely different."

But in response, Gaye’s children countersued Thicke and his producers, as well as EMI April, a smaller music publishing company owned by Sony/ATV, saying EMI April failed to protect the Gaye catalogue. While Gaye’s family members and the music publisher reached a settlement, they're still duking it out in court with the "Blurred Lines" trio.