How old is your wife and what preexisting medical conditions does she have that you are already familiar with? What kind of trembling ans is it only her leg??? If not an â¦ d she trembles when she's at rest, but it generally goes away when doing an activity then it could possibly suggest Parkinson's disease. Of course you are gonna need to see a neurologist for a proper diagnosis and obviously provide him/her with more information than what you gave here.