with a child that young you might not want to self medicate her. sit down and talk with her. maybe there is a reason why she wont go to sleep nightmares, stress, too stimulated of a day for her, something traumatic happened that she hasnt been able to tell you about. I would also contact the family physician and make an appointment. sometimes kids will tell their doctors what is going on when they dont their parents. the physician can also prescribe something that will help reduce childhood anxiety or prescribe a sleep aid or herbal aid and will be able to tell you based on her height, weight and age what dosage is appropriate for her.