From Sue Shellenbarger's "Work and Family" column in the WSJ:

...some parents aren't eager to have their kids grow up to be like them. Nearly three-fourths of physicians are less willing than in the past to encourage their children to follow their footsteps, says a 2005 survey of 736 doctors by Doctors Co., a Napa, Calif., insurer; fear of malpractice lawsuits is cited.