The adjective in this sentence is all. It's type is known as an indefinite adjective. Such an adjective gives us indefinite and unspecified informations. Adjectives as we know them are useful for the description and the modifications of of other words. Indefinite adjectives discusses those things which are not specific.
It's exactly as it says, the rich get richer and poor people are fircedbto have children. I don't know who "he" that's being mentioned is but maybe he is poor and he is okay with having children?
