An upcoming trip to the Doctor has Kathy feeling blue. Abig dose of purple is just what she needs. Barney and friends to the rescue. They get her laughing with some zany songs then lead her through make believe visit too the Doctor. The check up includes receiving a shot.This shows kids that it is not so bad when you know about them before hand. The kds sing and dance their way through Barneys famous "" feel good rules"" to keep those young bodies strong .