Haha. That clip was funny. I know what you mean about grabbing hands. When toddlers get excited they tend to tense up and quiver, don't they. My neighbours' kids came over last year to see my first batch of chicks. The 3 year old was holding one of the chicks, the chick started cheeping, the kid got excited and accidentally clamped down on the chick. Its little eyes nearly popped out! But no harm done, the chick was fine. I think its better to let young kids be 'hands on' with proper supervision than to keep them away. If you do that they'll just want to try and sneak in and play with the birds when you're not looking. 
By the way, VERY cute kid. And your coop and run look fabulous too. Lucky chicks!