I believe that if the parents can involve more and accompany the kids in ECA (not just only concern the result!), the kids can pick up more easily. So, I attend every piano lesson with my kid, and now though I cannot play the piano, I know what is good and which areas need further improvement. I can give the kid comments when she practises.
Let her trys to the play a song step by step. If she cannot finish a whole song, just play the first row. When she can play the first row without any problems, then proceed to the second row. This way can let her have more satisfaction. Don't cry la. Ask yourself, what is the purpose of learning piano?