One more tidbit to add:
My kids can be loud and wild...they tease each other at times...dd, especially is "spirited."
OTOH---I often get comments about their manners and maturity. I think it's because they are able to interact with people of all ages and because we're together so much, they have a constant example of how to act in the "real" world. For instance...they know to hold the door for the person behind them, or if a person has their arms full. They can go to a service desk and ask for directions or help. They can engage in everyday chit-chat with anyone: "Hello, how are you?" "I'm fine, and you?" As well as carry on lengthier, more interesting conversations. They are, generally, not intimidated by grownups, but just speak to them one person to another.
I *think* that's where the comments come from. I'm pretty sure the compliments would end if those same people heard them getting into the van, one jumping over the seat to get the 'best" seat while attempting to lock the 3rd one out. "IT'S MY TURN TO SIT IN FRONT!" "YOU SAT THERE LAST WEEK YOU KETCHUP HEAD!" "MOM SHE CALLED ME A NAME!"