Distributing properties of an estate that were put on different peoples names to avoid tax

I am willing to distribute my inheritance. We are 2 brothers and 3 sisters. My father made some properties in his life and they were put on different peoples names like me, my wife, my brother and his wife and my mother. This was only done to avoid any kind of tax. There were also some properties on my father's name. I would like to ask which properties should we include in the estate when distributing between my sister, mother, brother and me?