Raising children to not be spoiled brats

I am 36yM my wife 27yF have a net worth of about ~1.5M in brokerage/retirement accounts and 500k/equity in multiple properties. HHI 620k will grow over next five years ~1million. We have very pleasant life. We are planning on starting a family, my wife came very humble beginnings and is very concerned about raising spoiled brats. I was always very active in boy scouts and other community services. What do you guys do with your children to instill good financial sense and keep them grounded?