Sounds similar to my niece. WDW seemed out of the question to them especially after always hearing about the common $1k+/day cost. It's her, husband and 2 kids 6 & 7yo.
We started discussing a plan last year. Airfare's a big part of their budget and short ticket packages cost much more per day so we drew up a 8day/7nite free food offer at ASMo for August to get the biggest bang for their buck without taking the kids out of school. Take a longer trip every few years.
Room was $1200, tickets $2500 (with hoppers, required with food offer), and QS DDP would be included free. Not bad for a full WDW experience- onsite room/perks, plenty of food options included, plus enough time to pace a pleasant itinerary during the summer heat and rain. 2 days of FP's for each park reduces stress too. The room is spacious enough with 2 small children. The renovations are an improvement.
Travel: $1,000
Room/Hopper Tickets/Free Food: $3,700
Misc: $300
----$5,000 and that could totally work as a complete budget
Optional-
Add Memory Maker Picture Package: $170 (it can be a worthy splurge)
Upgrade to Table Service DDP: $400 plus $150 tips to do TS or character meals daily (fun but not necessary to have a great trip)
----$5,720
6 full days and 2 half days in WDW, roughly 7 days of magic.
2 Adults + 2 kids = $715 a day or $820 with optional extras.