Hmm, well i i dont think so. But if you read the terms of service it may be worth leaving your friends ads off your site.
The check your content, and if the banned your friend once before, for whatever reason, they may ban you to. Why chance it? I would not out the ads on. I would continue to build my site then submit to google. Once the approve you you can email them ad ask them if it violates the TOS, even though it may take them time to get back to you, at least you can have your site up and running while you wait.
Once your banned from google thats it!! Yes, there are other services you can use for PPC but I like google te best and I would make every effort not to give them a reason to ban me.
Like i said re read the terms of service for acceptable content.
Good luck!