TenniscoachIN....I think you got great advice from everyone. Looking to play like Henin, another shorter player, is a good idea. But as others said, do not totally pigeon hole her to any one type. Taylor her game towards not only her size, her strengths and weaknesses, but also the style of game which she enjoys the most. A kid playing the way they enjoy will go further in the long run.
My kid is only 4'8" so she attacks right now. She attacks every ball she can instead of playing by the back fence or hitting balls above her shoulders like most little ones do. As she ages we can adjust to her growing size and personality.