You need to handle it professionally, whether or not they do. The easiest way to do that is to use a pre-existing contract that has all of the terms you would prefer (or that you've agreed to). Take one from online, or one you've had in a prior position, and mock it up for this job - then give it to the family and say "this is the type of contract I've had in the past, if you have another format already in mind that's fine, but if not maybe this will be helpful. I find it really useful to put on paper all the compensation, benefit, leave, evaluation terms, expectations, etc..."
They're the rookies, you're the professional, you should feel comfortable acting like the professional.
Good luck.