Jon was fired from his job before the six were born & could not get unemployment checks. I always assumed they were poor since they needed food donated to them. How did they pay the bills with both out of work?
I don't remember Kate saying he couldn't get unemployment checks. She just says in her speech that he was fired over the insurance deal and it was legal to do that in Pennsylvania.
I also don't remember them saying that they needed food donated to them. When they had prayer requests on the old site, that was never on there.
Kate is clear in the speech that things were tough, and that they didn't know what they'd do, but in the end, God provided. Jon did stand in line at the Salvation Army once. She does mention that.
With all that said, to answer your question .. it's widely rumored and speculated that Jon's father helped out a lot when he was still alive.