slurring speech

My brother in law just turned 50, and within the last few weeks has begin slurring his speech.  He has always taken great care of himself, jogging, eatting well.  He has been to the doctor and been tested for MS, Parkinson's and Lou Gerich's disease all negative.  He is not showing any other symptoms exept for the slurring. We just saw him less than a month ago and did not exhibit any of this then.  He was recently fired rom his job (unexpected), and he has had some problems with thier daughter, could this be from stress?  We are all worried about him, and are looking for a possible cause.
thank you

[RJ233]

You can check with an otolarynologist. They work with the voice box and they may be able to find what is happening. Hope this helps you.