However it might be good to plan some activities for them, so as to keep them busy whilst adults are enjoying Champagne and nibbles.
Here is a selection of ideas to keep kids entertained at a wedding:
The traditional party bags that you can fill with colour pencils and little notepads, little toys, masks, old fashion games etc...
You can find a tutorial on how to create your vintage party bags here:
As always, Etsy is full of good ideas, for instance have a look at this lovely Wedding Activity Book:
Finally, if you have an outdoor wedding, I love the idea of creating a real space for children with colourful tipis, rugs and little tables and chairs: