I don't see the issue with the other children coming to the interview who do not require care. They are part of the same family so should the parent's get a babysitter?? Not something I would be happy having to do. As for grandparents attending, I have had this happen and don't see it as a big problem. It just tells me that the parent either appreciates another perspective and respects their opinion, or they are nervous and overwhelmed at searching for daycare. I don't think it is a reflection of their ability to parent, and I don't think there's anything wrong with dealing with a family on a day to day basis who may have low confidence issues. They need reassurance and guidance, not discarding as to much trouble to bother with.

The running around through your home though, that's another matter all together and unfortunately and I mean no offence by this, but that is up to you to take control of. The minute a child starts to act up, or family members start roaming your personal space, you really should stop things from escalating at that point. A firm but polite, please do not allow your child to leave this daycare room. How they respond to you then would be a good indication of the type of people they are. A lot of parents don't like to discipline in front of other people for fear of being harshly judged although I think most of us would respect that and see it as a positive thing. If you don't want them to run riot then don't let them and if after one request it doesn't get sorted by the adults present, then it's "interview time is over" as I don't want to deal with any family who doesn't teach their children respect and who don't discipline their children either.