Where once I would write in a pantsing only format and then figure the story stuff out in revision, I've changed that quite a bit - but not completely. I think I wasted quite a bit of time in my early years by only pantsing. I mean, I love pantsing, but revision was arduous, and often frustrating. I'd regularly cut, rearrange, or rewrite thousands of works in order to make a somewhat cohesive story. (Still working on that.)
With all my stories though, I now begin with a vague idea of a character and location. Who are they? What do they want? Why? What's stopping them? What will they learn? How will they grow?
Once I have those questions somewhat figured out, I take a stack of blank notecards and write a summary sentence or two on each. Then, I order and reorder them as I see fit for the story. I ask lots of "what if" questions as I fill out the cards and I don't always use each card. This process has helped me immensely.
It's so much easier for me to carry notecards and a pen (every retired educator carries a pen) and write bits here and there than it is to tote my laptop to the dance studio, or tennis practice, or piano lessons. I did that for several years. Sometimes I still do, but not nearly as frequently. When I have quiet time later (usually midnight) I can pants away with my notecards by my side!
Suffice it to say, if you have a busy life full of kids and all their activities and are trying to write a whole book, carry a few notecards and pen with you. I'll bet you can still feel attached to your manuscript and feel like you're making progress, and hopefully, you'll discover what I discovered.
Notecards keep me moving forward with the story, and the fun of "free-writing" within that notecard framework allows me to write fewer wasted words.
Good luck and keep writing!