By Brad Edwards

(CBS) — How do people celebrate the occasion when they turn 70?

Attend a concert, a play, maybe dinner?

One man is going for a run. A long run.

What Chuck Aron is about to do is pretty exceptional.

First, here’s why he’s doing it: He misses Paul Bracken, his brother-in-law. Paul died years ago of early-onset Alzheimer’s and would have been 73 today.

Chuck decided when he turned 70 he would run 73 different races in honor of Paul.

He’ll start with the Chicago quarter marathon this Sunday and end with the Chicago Marathon in the fall. In between he’ll be sprinkling in some 5K’s and one-milers.

Every mile he runs – running for Paul — he’ll raise money for Alzheimer’s.

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