We give Rachel a miniature piano that is nothing fancy, but it has different color keys and is easy for her to play with.  At first, she really didn't understand it when she watched us play for her.  Then, she started hitting the keys and realized she could make music.  It's really cute when she moves her hand side to side on the keyboard and her reaction when she hears the different notes she played.   Also, we have noticed she sort of makes humming sounds when she hears the theme for Tiger & Pooh cartoon.  It seems like she is trying to sing a long.  Her interest in music is still very fun to watch.