"He might drop his guard with children...he might give something away!"
"Well it was worth a try Number Two."
(Number 2 and Number 10 - The Girl Who Was Death}
It was worth a try. It seems that they were running out of ideas! The fact that he might drop his guard with children, that he might give something away. Number 6 knew what they were trying, hence the clown. And since when did Number 6 become a child minder? And Number 2, he was the only Number 2 to have a female assistant, but it may be supposed that the story dictated that.