"Someone sure has some funds to be able to support 15 kids."
Food must be a killer expense, but you probably save A LOT on clothes as time goes by. Kids never wear out their clothes, they can probably easily be worn by three kids in a row, as long as you avoid the trendy stuff.
People used to have big families like this all the time. And remember, the improverished third worlders do it all the time.
I only have one kid, so I better shut up now. Good luck to mom and dad and all their kids!
My husband's best friend in high school came from a family of twelve. His parents planned to have twelve right from the start and even bought the house for it. Food-wise it might have helped that they owned a potato processing company. It's probably because of his family that they started putting limits on milk on sale. When it was on sale, they would stock up for a couple weeks, which filled the whole shopping cart. Once a lady saw the milk and asked if they planned to drink all that milk. My husband's friend said, "No. We're growing a cow."