Moving away from home and having kids away from your family is a much bigger task than having kids in your hometown where all of your family lives. I get that it's normal mode of operation for a lot of people to move all over the country for jobs, but IMO that is where the biggest struggle comes from.
You take for granted being able to call a grandparent to pick the kids up from school if you're working late, to come over for a bit when you need to do something during an evening, to drop the kids off if you need to run an errand or even keep them overnight if you have to go out of town for work. That's before even figuring in extra-curricular activities and trying to get each child where they need to be.
My in-laws moved closer to us last year and it has been life changing for my wife and I who both work.