How to deal with a strong performer facing some personal issues

Problem

One of my direct reports, who had been a consistently strong performer, had a drop in performance. She did not display any signs of trouble during our weekly 1:1s. Instead, I found this out from a couple of engineers who worked closely with her. They cited several instances where her usual expected delivery was sub-par.

Actions taken

I decided to probe deeper into the root cause of this. As I had established a strong and trusting working relationship with her, I knew I could be candid with her. This was done in a non-threatening manner. I asked "How's your family? Is everything ok?" and "How's your son doing?". I never mentioned that her colleagues had complained about her drop in performance. Eventually, she broke down and cried and was forthcoming about her situation. Her youngest son had a growth abnormality, where one of his legs was growing faster than the other. She was extremely troubled by this and, as any parent would, placed some blame on herself. We worked together to help her understand why she was so troubled (her husband was not as distraught) and we talked about this during our weekly 1:1s. This allowed her to get it out of her system. She was very quickly back to performing at the high level that was expected of her.

Lessons learned

1. Strong performers may sometimes not be forthcoming about their personal troubles, as they may see this as a sign of weakness.
2. Build strong and trusting relationships with your reports during good times. You will need to cash them in during the more challenging ones.
3. Be sincere about wanting to help your reports. It should not be about the drop in performance but their general well-being. It is only when you demonstrate sincerity that you can find out the root cause of performance issues.