I know this is a wedding board, but I'm looking for help in negotiating an etiquette issue dealing with invitations for a baby shower.
DH and I have a 3 year old DD. His friends live out of town, and her family is throwing a baby shower for the couple this weekend. DH and DD happen to be traveling to his hometown this weekend, so he will be attending. We were invited as "Mr. and Mrs." - no child listed. Perfectly fine. We can make childcare arrangements (tricky because most of his family is invited, but do-able).
In this group of friends we've had many cases where the rule about "only who's on the envelope" was not followed. We received a wedding invite from one of them with only his name, so only he attended, and everyone (including the bride and groom) asked where I was
. My own bridal and baby showers that were held locally (as well as our wedding) had a variety of kids and friends that were not explicitly invited show up, which I didn't mind at all, but I know other people might. I promise, it's long, but there's a point in here! 
Is there a way to politely confirm DD is not invited? Maybe something with "we're happy to arrange childcare if not, but we wanted to clarify"? Or is that completely out of line? Based on our previous experiences, I would hate to send her off with a babysitter, and then DH gets there and people ask where she is, assuming he'd just bring her.
Thanks for your advice!