Mysterious Leg Ailment

Daycare was nice enough to capture on film Marino's mysterious leg issue, so I can share with all the doctors and others who seem to think I am insane, since he never does it when a doctor is around. If you know Marino, you know he is always moving, running, etc. There is no way he would be refusing to walk/bear weight on his leg unless there was an issue. Any thoughts/suggestions/opinions are welcome.