stereotype/labelling

as much as possible i don’t want to label or stereotype the kids as mini-rose or mini-mark (see story here)
but there are times that ‘generalizing’ them helps me in dealing with them
if there are things i want for migi to do, and he refused, even after bribery/threat
i have to resort to imagining him as mark, how should i deal this kind of issue with mark
how to make mark say yes to this.