They should be punished- and offered help.
State employment, for example. It shouldn't be a huge deal. I'd say that any parent who steals gets mandatory employment in some Public office for x amount of time, while also getting investment/wealth building advice so that they can get the cash they need while also facing the consequences of stealing the property of others.
First, it's important to establish what's right and wrong in society. It can't be wrong sometimes to steal and right other times to steal. If we all can agree completely that it's wrong to steal, as most people would say, then we would all agree that stealing is unacceptable, regardless of circumstance. That being said, we as a society should also provide help and support to those who need food, such as through food stamps, food kitchens, WIC, and other programs that will help make sure everyone is able to get enough food for their children to eat. A person who steals specifically for a child to eat should, of course, have a small punishment if that is his or her first crime.
It's hard for me to take a stand on this because it's can be a tough issue. While in this country a number of programs are out there to help with hungry children I'm not sure what it may be like in a number of other placed around the world that don't have these programs.