Brief Answer:
As explained below.

Detailed Answer:
Hello, and welcome to 'Ask A Doctor'

Thanks for posting your query.

I have gone through your query. Excessive eye blinking is usually a habit unless he does not have any eye problems which will have to be rules out after a careful examination by an ophthalmologist.

You just need to make him practice staring at point or some exercises which is eye rolling, diagonally and side to side to a count up to 30 count. With regular practice he will reduce blinking his eyes.

I would suggest you to visit an ophthalmologist to rule out any dry eye or other eye problems prior.

I hope this helps. Please feel free to discuss further if any.
Regards,

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