The Little Foxes (1941)

Regina Hubbard Giddens (Bette Davis) and her scheming brothers, Oscar (Carl Benton Reid) and Ben (Charles Dingle), plan to get rich from a cotton mill, but first they must tap into the wealth of Regina's sickly husband, Horace Giddens (Herbert Marshall). The trio attempts to marry Regina's daughter Alexandra (Teresa Wright) to Oscar's son Leo (Dan Duryea). When that plan fails, their schemes devolve into theft and blackmail, driving an irreparable wedge between family members.