Exempt from Filing a Return

I am helping a friend with his return and his income is low and doesn't have to file. His 2018 income from work was under $10,000. He had no other income. He paid $160 income tax during the year and only had health insurance coverage for 3 months because he couldn't afford full year coverage. Does he have to file due to not having health insurance coverage for the full 12 months? What are his options? 

PS: He is married, but intends to file MFS. His wife's only income was from disability benefits ($6,000) for her son. She also had insurance coverage for 3 months only.

Thanks