Mine is general chitchat at the door too and mostly my parents trust that if their child is coming and going relatively happy that everything is fine. I let them know mostly about anything out of the ordinary so they can plan their evening like child ate very little, or was very tired and napped extra long or had more than the usually poopy diapers. My parents themselves have all become friends and the kids are treated like a group of brothers and sisters that just go to different homes at night. The parents will ask how a child that has been sick is feeling or comment on a child that seems fussy from teething and offer child empathy, etc. It is so nice having this closeness because then they can support each other as parents too. I do send home seasonal newsletters - usually every two months and outline what we are doing curriculum wise, changes, birthdays, etc.