All of Graves' aurors view him as this gruff unapproachable boss who is fair but suffers no fools. So naturally they are surprised to se him interacting with kids and being great at it. Maybe he is able to calm down and ask questions from the kid who saw a crime. Or he is every kid's favourite during Take-your-child-to-work day. Or maybe in AU where Credence is an actual child and they rescue him from Mary Lou and keep him in the office until Wizarding Child Services arrive, and Graves is only one who can get any reaction out of him and Credence follows him around like a lost puppy.

But no-one wants to ask obvious question - Who replaced Graves? - considering you-know-what.