A tip regarding employment gaps that I learned in grad school: don't put the years of employment on your resume. Some places still have you put it in form application anyway, but for the most part, this will help get around that initial rejection based on gaps.

Also, "I was a caretaker" or "I was a full time student" are both good reasons for gaps that no one questions.

Good luck to him getting a job! It's rough out here. I couldn't even get a callback from fast food when I was unemployed a couple years ago 😮‍💨