Frameworks and examples now exist showing how to gain this freedom. Jacob Lund Fisker[0]'s ERE[1] in particular is an interesting system theory based approach .
Most if these schemes are geared towards singles. I haven't seen a guide to FIRE for an average single income family with children.
I invite you to read the book or read one of the interviews with the author. It goes so much wider than FIRE. Rather than a guide, it's an invitation to build your strategy. That should workas an individual or a couple, with or without children.