We had an intern come and spend 3 months with us.

She was skittish about doing ANYTHING on her own. Most of our interns shadow for the first 2-3 weeks and then slowly begin to work more and more independently on small projects that can be done with some supervision and oversight. Not her - she never moved beyond shadowing the entire 3 months.

A few months later she graduated and asked if I would be willing to be a reference for her.

I told her I was willing, but that it may be in her best interest to look elsewhere - and then expressed the concerns I'd seen while she was with us and indicated I would feel obligated to share those with anyone who asked me for a reference.

I don't know if she used me as a reference - I do know that no one called me.