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 in any way. The test reveals that neither is Luke's biological parent. What must happen now?