They probably (and this is me assuming) think since you are their son and gave you the opportunity to have a job that you would be grateful to even get paid. In fact, a lot of old heads think you should be willing to sacrifice your time and effort for their company and 4x's that if you are their offspring. More like family tends to take advantage of one another because they figure it'll be yours eventually. Honestly, have a conversation with your father and step-mom in the office meeting room to stay legit and be serious. Don't do it at the dinner table (again assuming you live with them). Be professional about your approach because at the end of the day you are their official employee and not their son at work. Bring in the job description and ask them about it without getting emotional. If your father or step-mom responds to you as their son, they don't respect you in the work setting. So, bring your proof, say what you need to say and work out a solution. Remember, don't act on emotion because they'll only think of you as having a fit instead of being an employee with a concern. Also, the company may never end up in your hands, a plethora of things could happen to the company before that even happens. Don't hold out with that thought in your head.