|No such thing as a small change
Why not just teach this Child?
It didn't understand use strict; properly - then you'll provide it with good reading.
Much worse will be if this child refuses to learn and did not respect your programming practice when you're explained it about 'strict' - but presumably this is not the case. You just tried to not get angry but anyways got angry when a person did not understood obvious for you thing.
I learned from many articles here, that good programming is about learning many things (programming techniques, behaviour in the office, corporate etiquette, and many many things).