While we were visiting my family in Kansas City this summer, Lincoln decided that he had enough of his pesky little sister and commissioned his Nana to write a sign for him. Then he drew the pictures - so Ellie would be able to understand what it said, naturally. The pictures are a number 4 (meaning you have to be 4 years-old), Ellie's face Xed out, and a railroad crossing sign (he was playing with train tracks).
He posted it up and then showed Ellie the sign - pointing to the words and "reading": "Ellie don't come in". Then Ellie would say "Come in!" very happily - to which Lincoln would say, "No! Ellie don't come in" and she would repeat again "Come in!" It basically continued like that for a while! Too hard to keep from laughing at these kids!