PLS help, what is my right?

My mother remarried in china. She has our 3 kids. My mother has some money and houses. My new father has some money and houses as well. He did has 3 kids too. If my mother die or this new father die, how the money and properties divide.Can we let them to do a living well? What if they want to change this living will? What we can do to protect the money my mother had it before?