4-month résumé gap, advice? (update)

I have been out of work for 4 months and worry about the gap. I am nervous about being filtered out. Did anyone get past it?

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

A short, honest line such as 'family caregiving' is enough for most employers. They mostly want to know you are ready now.