This has been an interesting thread to read.
The OP was looking for advice on how to retain a valued employee. Otherwise I assume the post would never have been made.
Eight replies say fire, two say get rid. At no time has the OP said the employee has violated attendance policy, in fact, quite the opposite. I find this quite disappointing and reflective of the plantation mentality where people are disposable. And then people wonder why turn over is so high and no one wants to work for the company.
I found six responders that were helpful.

Thank you for leading. I will follow and hope to lead others as you do.