Two of Marvin Gaye's children sued Robin Thicke and his collaborators on the hit song "Blurred Lines" on Wednesday, accusing them of copyright infringement and alleging music company, EMI failed to protect their father's legacy. Nona Marvisa Gaye and Frankie Christian Gaye's suit is the latest salvo in a dispute over Thicke's hit and whether it copies elements of Gaye's song "Got to Give It Up." Their lawsuit seeks to block Thicke and collaborators Pharrell and T.I. from using elements of their father's music in "Blurred Lines" or other songs. Thicke has denied copying Gaye's song for "Blurred Lines," which has the longest streak this year atop the Billboard Hot 100 chart and has sold more than six million tracks so far. The suit also accused Thicke of improperly using Gaye's song "After the Dance" in his song "Love After War."