Gan Lu caught Nelson and Mark having a sweet little 'check-up'. Dr Nelson knew just what to do with the stethoscope.
Then it was Mark's turn to be the doctor, and he didn't seem quite so sure what to do. Nelson had to help out...
Dr Mark lost interest in using the stethoscope and had a think about alternative treatments for his patient.
Uh-oh, it looks like he thinks surgery is necessary!
Good playing, boys - what a fun check-up.