I will say do it......as long as you can pay cash without missing payments on bills or pulling from a fund you have designated for something else (medical bills, housing upgrades, etc...) We didn't vacation until my oldest was 7. I never thought we could afford it. Then I got sick of seeing everyone else having a blast and decided we'd do it or bust LOL I saved each week, anything I didn't spend went into the savings. In the end I didn't have much (about $1000) but it covered our room and some gas. My parents went with us (in their own room) and paid the other half of the gas. My food budget was just what I would've spent that week anyway. We went to Florida, stayed in a Super 8 about a mile from the beach, and had a blast. Seeing my kids in the ocean the first time was awesome. Also, I am a "super tourist" (my mom's words) and had researched out fun kid things to do that were FREE or next to nothing in cost. We visited a children's museum, went to eat at Fudpucker's (kids loved it, adults were "meh"), etc... After that we've gone every year. One year my parents rented a condo in Myrtle Beach and we tagged along and paid for food and entertainment, we split gas. The next year was all on our own. DH had enough pts to get 2 free rooms for 3 nights at a Sleep Inn on the Beach. First ever vacation for him (he won't vacay with my parents) and he was sold. Last year we went to Lake Michigan. Again, I scouted out inexpensive but nice rooms and had found cool places to visit on the inexpensive side. Days at the "beach" were free, we even packed a cooler for lunch. Still, we are spending not much more than that on our WDW vacation. We are staying in an offsite condo, only eating onsite 3 or 4 times, buying discounted tickets, and driving down (flying six cheaply? LOL not that I've found......yet.) One year we even just went to Nasville for the weekend and did the Nashville Shore waterpark.
You may not be able to do Disney (or you may, you have to factor in the expense of getting there and the tickets but you can usually micro-manage other details to cheapen them.) The thing is you may have to do a 3 day vacation - Fri, Sat, and Sun with a hotel room Fri and Sat night. It can still be wonderful and the bonus is - the one working only misses Friday!! The year we went to the beach with DH he missed two days, Fri and Mon, because we stayed over a weekend to accomodate his work schedule. You don't have to be gone 7 days, do what works for you.
I wish I had made that realization earlier and we had vacationed earlier. For us, it has really helped create a memory that bonds us. But, again, we only do it when we can pay it upfront and still meet other repsonibilites. Oh, and I had to add - We have friends who are better off than we are and they go into debt to vacation

They also don't know how to budget for a vacation and want to do it all "maximum experience". They refuse to drive, flying is "nicer". They refuse to use a condo to eat in (why bother renting one and having the full kitchen? Though I will admit we rent 2 hotel rooms sometimes because we just need the space) because they are on vacation and want to eat out, etc... Sometimes you have to live within your means which means vacationing within your means, too. I'd much rather be cooking in my condo on the beach or offsite near Disney, or taking sandwiches I made to the beach at Lake Michigan than sitting in my living room all summer but that is just me (I mean, really, I'll have to fix food at home so why not do it somewhere fun? LOL)
ETA - Dave Ramsey is great BUT 25% of some people's income would not approach covering a home/apt in a safe neighborhood. Do what you gotta do but don't put your kids in danger to have a cheaper house payment. Also, when my kids were younger I, basically, had to stay home. I tried to work and 2 kids in daycare ate my check. That was okay except if I had to miss work when one was sick (and still had to pay daycare to hold their spot) which meant I had to "borrow" from DH's check to make the daycare. Then it ceased to make sense. Also, I would LOVE to go to school but for me it IS about finances. We make "too much" (insert sarcastic laugh) for me to get grants and I work 8 - 5:30 every week for a job that, once insurance is taken out, leaves me with about 1/2 my pay. BUT the insurance is good. I could quit and DH could go back to carrying insurance but it is my $500 good insurance vs his $1200 crummy insurance. For us, with kids who do go to the doctor and who have orthodontics, etc... it really isn't worth it right now. And I don't live anywhere that offers night classes for 100% of your degree so I WOULD have to quit at some point, for about a year. I may do that later, if circumstances change, but right now that would be a financial disaster. I'm just saying you can cut corners and cut corners but when there is nothing left to cut you have to work with what you've got. OP may not mean she can't go to school EVER but right now it may be her reality and only she and her family can make that decision. They may not have to live where they are for life but right now it may be their best option. Again, that is really only something those in her home can decide.