SWITCHED AT BIRTH
This is Not a Pipe
S1 E1:
Bay Kennish discovers during a biology class that she has a rare blood type which is different from her parents. Intrigued by her new discovery, Bay convinces her parents, Kathryn and John, to visit a genetic testing facility where it's confirmed that Bay is not their biological daughter. There was a mix up at the hospital and both families took home the wrong babies.