Dutchman and The Slave Lesson Plan

Why does Walker tell Grace that their daughters are dead? What are some possibilities about this statement?

One possibility is that Walker tells this to Grace in order to hurt her, despite the fact that their daughters are still alive upstairs. Another is that Walker says this because he is planning on leaving them in the bombed house, and he knows they will soon die anyway. A third option is that he already killed them before Grace and Easley arrive home. This last possibility brings to mind stories of slaves who would kill their babies in order to “save” them from lives of slavery (inspiration for Toni Morrison’s Beloved). However, it seems less possible than the others...