Ava DuVernay’s tweet pays homage to Michelle Obama’s slave ancestor

Image: Cheriss May/NurPhoto via Getty ImagesFormer First Lady Michelle Obama's family sure has come a long way in five generations. American filmmaker and Selma director Ava DuVernay shared a compelling tweet paying tribute to the former First Lady's great-great-great grandmother, Melvinia "Mattie" Shields McGruder, who was born a slave