Help identifying movie (poor family, keeps winning contests etc.)?

It's an older movie, and all I remember about it was that it was about a big family that was poor, and in one scene the mother won some sort of competiton in which she got to fill her grocery cart with as many items she could in a certain amount of time, and they got caviar and all this fancy stuff they never had. I think she would enter in these competitions and keep winning or something, and there was one person in the movie that was in an iron lung. Anyone know what I'm talking about? Thanks!