Originally Posted by Finance Dave
First off, congrats! It's also great that you are planning and thinking ahead.
Too many things can change between now and then. You never know what will happen with tax laws, health insurance reform, what if you or one of your kids gets a serious illness or needs an expensive surgery?
I think it's great to head towards your plan, but try to remain flexible. Set interim goals, and then if you miss one in, say two years, you can ramp up savings or reduce spending or whatever is needed to get back in line. The nice thing about planning is that you can make adjustments...such as working longer or getting a part time gig in FIRE.
Dave is right. There are so many unkowns. I tend to hang-up on the least likely which is ironic. Like oh they will be Conference All Pro sport with huge expenses, or they will go to best private school in town, or they will do the unthinkable and we face huge financial consequence somehow... then I breathe.
The idea of continually dropping more into the "later" bucket every single week has helped us sleep. But best to plan now then be broke later.