“Daisies don't come in blue,” he said, and gave the paper back to her.
. . . . “Pretty flower,” she said. “Yay Abby!”
YES! She has already learned how to deal with Sherlock! Ignore most of what he says, especially if it's insulting.

Silly Sherlock! Just because he would delete things like dealing with children doesn't mean Mycroft would. Mycroft excels at manipulating people; Sherlock has some of those skills but doesn't care enough to develop them fully.

The smarter ones usually sleep less. It's the truth.