Yesssssss!!! (Followed by a Small Squeak of Fear)

My resume's first foray into the job market hooked me a big one! I now have an interview in early June for a very nice job with a non-profit organization that advocates for and supports military families. The job is mid-level and will involve interacting with families, military leadership and government (both elected and appointed). As I understand it, there are some supervisory duties as well.

I believe the interview will be face-to-face. I have about two weeks to prepare...

Any advice?

Also... The most important requirement for the job seems to be a knowledge of the issues facing military families. Since I can't say, "I'm a military brat," or "My husband has been in the military for 10 years," how do I prove my competency in this area during the interview?

And considering that in the last two weeks I've been told by multiple people that I look anywhere from 12 to 26 years old, any advice on getting them to take me seriously in a face-to-face? LOL!