My Broken-Hearted Valentine - S3-E18
Other mistake: When Steve is wearing his Cupid costume and waiting for Laura in the Winslows' living room, the doorbell rings. He is obviously excited and ready to pose before seeing Daniel there. This does not make sense because Laura would not ring the doorbell to enter her own home. In fact, she does not ring it when she does arrive shortly after Daniel.
Answer: It was just cancelled. Read more here: http://www.kellie.de/end.htm.
Myridon