Despite a public divorce  last summer,  Nas and Kelis have managed to keep the details of their separation private. Now the rapper is taking his ex-wife to task on a new song.   Nas addresses Kelis in a newly-added verse from “Strong Will Continue,” his collaboration with Damian “Jr. Gong” Marley from their joint album Distant Relatives. The former couple has a 6-month-old son named Knight together.