Hi Blaise,
To feed so many people you need to think of foods that are cheap and healthy. If the father is ill he needs foods that are easy for the stomach to process. If you have a big pot for cooking in soup is always good, a little bit of meat and lots of fresh vegetables. Not too many spices.
Add some bread to dip in the soup.
Your body absorbs goodness from soup very quickly.
I'll think of some more for you after I finish a few little jobs.
Cheers,
Andrew.