I saw a very shy 2-year-old in the Peds ED.  She was so shy that she only opened her mouth a little bit when I asked her to, and looked scared during my history and physical.  Since her complaints were fever and abdominal pain, to test for peritonitis I then picked her up and lifted her up and down while saying "Whee whee!!"  (I couldn't lift her up that high though since I have limited upper body strength).  As I did that, she finally smiled!