Switched at Birth

On the same night, Milford Maternity delivers Morgan--businessman James and Sarah's son--and Linda's boy Luke Wells, whose father Darryl Moncton has already left, so mother and son will live with her parents. A nurse switches the babies' nametags. Two years later, Darryl returns but denies paternity. He accepts a DNA test if she promises that he doesn't need to be involved in their lives anyway. The test reveals that neither is Luke's biological parent. What must happen now?