One option used to be to create an irrevocable trust funded with a life ins. Policy on the farmer to cash out the non farmers. Don’t know if that is still a viable option, but the idea was to have the farm pass to those active on the farm and have cash pass to the others.
Another option is for the parent to specify which part of the farm goes to who without buying life ins.
Rarely good idea to leave farm to all equally hoping they will agree among themselves. Only takes one stubborn heir to mess it up.