I will be having a babysitter at my wedding to take care of my son and all the other invited children. Would it be tacky to put a note in the wedding invitations asking parents if they might use the wedding babysitter?
It wouldn't be at all tacky -- in fact, it's really gracious. If you're planning on including this info in your wedding invitations, handwrite a personal note (don't put in printed cards) to those with children. Say something like: "Marcie, we're having a babysitter at the reception, so I'd love for you to bring Brian along! Let me know if that sounds like a plan. Can't wait to see you! Love, Anne."
If your wedding invitations are already stuffed to the gills, another option is to call the parents and let them know about the babysitter. Either way is completely appropriate, and the parents will definitely appreciate your thoughtfulness -- before and during the wedding reception.
See More: Kids at Weddings , Wedding Reception Ideas , Wedding Receptions