A future brother-in-law who won't get motivated?

I really don't understand my future brother-in-law. He graduated from high school,went to Temple University,majored in acting,and he holds a bar-tending degree. He can get a very high-paying career,however he keeps on settling for medium wage jobs like Rite-Aid,Shop-Rite and Arby's. We moved to Harrisburg back in August and he still haven't gotten a job. We are trying to help him but he's just not being pro-active.Instead of calling back for a interview,he is on the computer all day talking to women.I'm going to school to be a RN so me and my fiancee can better take care of his elderly parents(we live with them) and I'm worried that once me and him get a house of our own, then his brother will mooch off of us. I don't mind sharing a house with my elderly in-laws,but does it mean I have to put up with my 27 year old brother-in-law who won't do something with his life or move out? How can I get him motivated?