The quick version of what happened is that I gave a colleague from school a reference at my company, and he ended up getting an internship. My boss only offered the internship because I asked, so I feel a bit of personal responsibility for the result of this being good.
When he asked me my thoughts on my friend before hiring him, I told him clearly that I had never worked with him in a technical or professional setting, so I couldn't attest to his technical ability, but I thought highly of his work ethic, which is still true.
The problem is, his technical skills have turned out to be a bit lacking, despite him being a senior in a decent Information Systems program. For instance, he was assigned a task with an estimate of 20 hours. Realistically, it should have taken only 3 or 4 hours, but obviously being new, he was given some extra time to adjust to the codebase, etc. It has now been a full week and a half, and the task is still not very close to completion.
I've tried to help him out with it here and there, but I'm pretty busy myself and don't want to hold his hand through every step, so that he relies too heavily on me. I don't believe it should be my responsibility to train him on basic things.
Then the other day I was surprised when he was making a few professionalism blunders such as loudly making a somewhat non-PC joke in a loud voice while I was at his desk trying to give him some pointers, and the neighboring cubicles were definitely in earshot.
I've spoken with him privately about not saying potentially offensive things at the office (well really anytime), but I'm afraid that this behavior and performance will reflect badly on me. Technical issues aside, the last thing I expected was to have to worry about his personal behavior.
He still has--presumably--a couple months left in this internship. What can I do to minimize any damage that his behavior and performance may have on my reputation? Is this something I should even be concerned about?