You will need for the family to have a stipend each month or year for the raising of your children. This could be used for a family style vacation, clothing, sports fees, bicycles, toys, bedroom furniture, what ever the couple thinks is needed. They would not need to be accountable for this money unless someone thought the kids were being neglected or abused and the money being stolen.
The family I was named by had it set up where the money each year would be in the hundreds of thousands. He was one of the top 2 geophysicists at a global wide company and his income was 4 times what hers was as a professor of nursing at a local college.
They had this set up very well. Their attorney had specific reasons in the paperwork as to why they did not want their families to have guardianship/custody/supervision of their children, mostly they figured the only ones to contest the will would be the ones wanting control of the money. They listed many reasons and had the attorney make it as iron clad as he could. We had the papers on file in the county court house in the section for wills and such. I am not sure of what happened to them once they were signed. A copy went to the attorney's office for sure.
We would be allowed a certain portion of the money as "income" if we wanted it to be. There was written in that once the needs were met that would could use money for ourselves. They did not set it as salary due to taxes and such but it was written we could spend part of it on ourselves, a treat per say.
The kids had their own accounts set up and the money was not able to be handed out to them until they had completed college. All had to go, it was required. If they wanted the money they had to prove they could support themselves and make a commitment to "life".
Their needs and some of their wants would be taken care of by the monthly/yearly income from the assets of the parents.
The house was the kids and they could not do anything with it as far as selling it or anything until they were all adults and they could come to a consensus. They didn't even have to move out. The house was 3 1/2 levels and had something like 8 bedrooms and 3 1/2 bathrooms. There was even part of the basement set up like an apartment that could be used for an adult couple later on.
The couple never had any accidents and they did often travel separately when flying. The mom and dad divorced later in life and they are still living and have many grandchildren now. The house burned to the ground a couple of years ago too. The mom and kids still living there got out safely but the lost everything they owned. Just walked away with the night clothes on their backs.