I think it's an opportunity. Maybe ask the parent to step out for the interview part and be there for the informational portion. That way you can "sell" the parent on the job too if the youngster is a good candidate. A parent will very likely take better notes. That said, I was happy to nap in the car while my kid did their interview. It would be awkward in my case for a parent to show up though because most people that apply with me are in the 35-70 range ;)