If I'm a potential recruit for the army and the son of a Marine (which I am), is it stolen valor to wear military apparel?

I don't recommend you wearing your dads old patches, but if he is ok with it. Just keep in mind there is a great big world out there, with tons of interesting people out there from all walks of life, just waiting to be offended by something you are wearing.

Al-There's a big difference between wearing your Dad's old jacket, and posing as an actual U.S. Marine-I think you're safe. Still, people used to have common sense, and could tell the difference between a proud son and a poser...These days, common sense is not so common.

I'd suggest that if you're close to enlisting yourself, try enjoying "civvies" as long as you can, and spend a few months sampling all of the things you might be leaving behind for awhile...get to know the "you" without the military in the background (take some advice from the son of an Army NCO).

When you show up for processing...leave all of that stuff behind. Wear clothing that stands out as little as possible, and definitely NO military items of any kind whatsoever-not even "Grunt Style" shirts! Within a few hours...you'll be in your own uniform and building your own career to be proud of.

No it's fine. If anyone asks just be honest about, you have family in the military and you're showing support.