Your family's welfare has to come first- Not only is there the loss of income to think about, but health insurance.
Instead, I'd suggest spending the next 6 months living below your means, and putting the money aside. You don't need much, but enough to comfortably live on for a few months, supporting your family.
Price out private health insurance- This is cheaper in regulated states such as Massachusetts, but your situation and location will vary.
After you have a few months salary put aside, then you'll be in a stronger position to take time away from a job to start a company.