The estate for the late Michael Jackson is at war with the pop legend’s baby sister, singer Janet Jackson, over one of the songs on her newly-released Greatest Hits album, Number Ones.

According to Entertainment Tonight insiders: The song in question is called “Make Me” and features a lyric that reads, “Don’t stop till you get it up.” The source has told ET that Michael’s estate is questioning Janet’s right to use the lyric because of its similarity to his song “Don’t Stop ‘Til You Get Enough,” featured on Michael’s album Off the Wall.