Brief Answer:
Read below.

Detailed Answer:
I read your question and I understand your concern.

Before I mention symptoms I would like to tell you that only about 7-8% of cases of Parkinson disease are of a familial genetically inherited nature and those cases usually manifest at an earlier age, before 50. It is a common condition which means that it is not rare for one to have a parent with Parkinson's, it doesn't mean much. So unless there is a really strong inheritance in your husbands family for several members I wouldn't worry much on that regard.

Typical symptoms of Parkinson's are
-tremor, often hands/fingers, appears during rest and improves on movement, usually starting on one side and only later on in the course of disease becoming bilateral
-slowing of movement (bradykinesia)
-rigidity, muscle stiffness
-change of posture and balance
-changes in walking, small shuffling steps with reduced accompanying movements of the limbs
-changes in his writing
-changes in the speech

These are the classical symptoms related to impairment of movement. There are also some early symptoms which are present before these movement symptoms like: loss of smell, constipation, changes in behavior and sleeping disturbance which can include vivid dreams and nightmare. However nightmares alone are definitely not enough to make a diagnosis of Parkinson's, only if other symptoms and signs appear as well.

I remain at your disposal for further questions.

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