Jon Marshman, aged 10, loves to ride bikes and climb trees. His grandparents have a beautiful grove of sycamore trees and he visits her often to climb trees with his cousins and eat his grandma’s cherry pie. Sycamore trees are some somewhat brittle, as Jon discovered a couple of months ago when a limb he was on snapped and plunged him to the ground. He landed in the grass except for his elbow which took a glancing blow on a rock. His grandpa took him to have his arm X-rayed, but luckily nothing seemed to be broken. The doctor told him to take some Tylenol and rest his arm. This was two months ago, and young Jon and his mother are in your clinic. Jon’s arm is still hurting and is warm and swollen just distal to the elbow. Jon has had some nausea off and on and has been running a fever. He has stayed home from school for two days last week and laied around all weekend. What could be Jon’s problem? What tests can you run? What help can you provide for Jon?