I agree with those who would approach the parents from a safety standpoint. You can get your point across (hey, watch your kid) but from a standpoint that puts you and the parents on the same side (I sure would hate to see this little fellow/gal get hurt - could you please come collect him/her.)

True story. I was officiating a Jr. high basketball game. Small gym, bench seats all the way to the edge of the court. I'm about midway when a fast break comes rippin down the court and I turn to lead the play to the far basket. 10 feet in front of me a precocious toddler gets away from mommy and makes it about three feet onto the court (right in front of me.) In what could rightly be called my greatest athletic move, I swooped the little kid up and handed it to it's parent without even breaking stride. At the next dead ball, I looked to the sideline to see what the result was, and the kid was in a clamp-lock that would make any wrestler proud. Made it through the rest of the game just fine.

Big amps, electric cords, mic stands and all the other paraphanelia are definitely not a place for wee ones.

Freightdawg