Do I need a professional photographer to take my head shot?

I am a high schooler looking to get into being a background or extra for now in movies or television, and I was wondering if I need a professional to take my head shot or whether I can just have someone I know do it. Is there a difference? I don't really know much about it, though I've heard it can be pricey. I have an older cousin currently at photography school who has done some modeling and a couple family friend weddings on the side, would using him be okay?