What kind of istance do my children qualify for if their dad is in prison?

Their father has been incarcerated now for four years for murder. I do receive foodstamps and children's medicaid, but I need financial help. I tried to work a second job, but my medicaid and foodstamps got cut off!! I can't win for losing. My childrens grandparents won't even help!! Someone mentioned that since my children's dad is in prison-they qualify for monetary help, is this true? please help thank you