A lot of weddings often have kids running around -- much to the chagrin of the brides, grooms, and the children's parents. One sure fire way to bring them bounding to the dance area is to have the bride and groom dance with bubbles floating about -- kids are kids, and they can't resist bubbles. Having bubbles floating out of a machine is too irresistible.
Another sure fire way to bring kids to the programme area is to have a cake with attractive trimmings or a really nice topper. We once had a kid who cried for a good 10 to 15 minutes because he wanted the topper. Of course, we couldn't give him the toy-looking topper till after the cake cutting ceremony.
Other kids just like being part of the action so they will join while the couple is dancing or they will have their own shadow puppet play using the projector while we are showing the onsite photo slideshow or the same day edit. Some think the couple's couch would be nice to sit on or sleep on... :)
These and many others constitute couples' reasons for adding lines to their invites pertaining to the ceremony and reception as overall adult affairs. Some even remove the kiddie entourage altogether, just so they can ensure solemnity during the ceremony. (The dreaded crying baby during personal vows...)
Below is a suggested verse that lets people know you'd rather have adults only on your big day.
Those who can't prevent kids from coming to their big days should be prepared to just take things in stride. After all, kids are cute and usually, whatever they do, they remain cute. :)