DD13 asked a friend to come swim at our house. The parents said not unless her younger brothers and sisters come too. Um, NO. You're talking four extra kids under the age of 11. I have four children (she's the youngest) and I never did things like this. I think kids need to know their brothers/sisters may get invited to something your not sometimes. I'm not trying to be mean, but really. I think that's unreasonable to expect me to agree to that. (And no the parents weren't going to stay and watch them either.)
Did you put stipulations like that on your kids invitations to places?
Never, with the girls (4 years apart). DS was 10 years after DD2, so the only time either girl took him with her is when she knew she had to babysit, and made plans including him.
DD2 had a birthday party, invited her whole class. One girl showed up with her 3 younger siblings. DD2 was in 2nd grade, and the younger kids were in K, Pre K and one under 2 years. They walked over, across a super busy road, to come to the party----no parent. The mom didn't call to check and see if it was ok, nothing. Oh, and no diapers for the under 2 kid.
DH took them home after the party, and they kept showing up at our house for the next week. No diapers, no snacks for them, nothing. They would show up at 7am and DH would take them home at 6pm, when he got home from work. No one would answer the phone.
I finally had to have a talk with the dad, who worked nights and slept days, so he had no clue what the kids were doing. The mom didn't work, but she didn't do anything else, either.