*cringe*
Been there, done that.
If, as Pondlife says, the other instructor is mature you will probably be OK. Perhaps the CFI would be a better sounding board for the Stude?
Worse would be giving observers the impression that you are "White-ant"-ing the other instructor.
I'd approach my CFI.
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Bendo: "This program has performed an illegal operation and will be shut down..."