Yes! As long as they are well behaved and you let us know ahead of time as we plan to have a "kid station" with activities!
If your invitation says "And Guest" then yes, if not we would prefer if it was just you. If you aren't 100% sure just send me an email and I'll be happy to help!
Casual- we want you to be able to look good and still be comfortable! All we ask is please no white and remember there will be children so keep it appropriate.