How do I handle a long gap on my résumé? - any advice?

I took time out to care for a family member after working as a warehouse supervisor. I have been trying to stay organised about it. I am nervous about being filtered out. How did you handle it on your résumé?

I listed the volunteering and course under the same dates and kept the explanation to a sentence in the cover letter.

Thanks for writing this out. I went through something close to it last year, and it settled down once I kept a simple log of every call and form.