Oh gosh, having 3-kids ranging from 4-13, I've pretty much had more than I can count.
Well, when my daughter was 6, we were living in Panama and had gone through a bunch of things trying to get custody of the son we adopted. She had been through all of the psychological and psychiatric exams and even through hiring the private investigator to see if he could find the bmom that left him in the hospital.
We went through all of this and finally got custody. The friend of mine from the Dominican Republic that had been our interpreter through a lot of these visits, was holding our son with me and my daughter standing there, all talking.
A little old lady walked up to my friend and said, you've got the most beautiful little boy. She said thank you, but he's not mine, he's hers, motioning to me. The lady looked at me (blonde hair-green eyes) and then our son (hispanic) and back and forth several times. She then spoke up and said, "he must look just like his father".
Of couse, then my daughter spoke up proudly, in a very loud voice, "Oh, we don't know who is father is". My husband and friend's husband were about 10 feet away hearing all of this and were rolling on the ground. The lady's face was priceless.
I should have learned from that moment, that if my daughter thinks it, it'll come right out of her mouth. At 13, it's still the same.