My mother owned 20 acres and a nice trailor on it before marrying my stepfather. After marrying, they built a new home on the acreage and sold trailor. My step dad is in bad health now and wants my mom to sign the land over to him so he can leave everything to his sons, one he had proir to the marriage and one they adopted together. She won't do this, but could his son from previous marriage take home away from my mom. He won't give her survivorship clause. They both worked and paid off home.

In whose name is the property right now?

The land is solely in my mothers name, home is in both names.

I'm not sure I understand. The home is not a trailer, correct? If it's not a trailer then the home cannot be owned separately from the land.

My mother was deeded the property by her parents prior to marrying my stepdad. They later married, she already had a trailor house on this property, which she owned. They lived in trailor, made a loan in both names and built a home on this property. The land was not and is not now on the deed for the home. All property taxes come solely in my mothers name, she pays them, this includes property tax on the home built there. The home that was built there after their marriage was added to the value of my mother's land at courthouse and she solely has been taxed for it since. The home is paid for now, loan for home was in both their names. Land that was deeded to my mother, which house is built on, states that at her death land goes to her heirs. My mother had four children prior to marrying and building home, gained a step-son when she remarried and her and my step-dad adopted a son who is 24, disabled and lives with them. Step-dad wants to give his part of home to his sons, natural and adopted. How would this be divided? And could my mother be made to go in debt to pay-off stepsons interest, if he has any?

The way you've described the situation here, your stepfather does not own any interest in the home. His name may have been on the loan that was taken out to build the house but since his name is not on the deed he is not an owner of the home or the land.

When a house is built on property (rather than a trailer being placed on the property), the house becomes part of the property and cannot be owned separately from the property. Since your mother never prepared a new deed adding him as an owner of the property he has no ownership interest in the house that is built on it.

The first step your mother needs to do is to decide who she wants the house and land to go to after she's gone. The second step she must take is to see an attorney who is experienced in wills and estate planning so they can conclusively determine the status of ownership of the property and then she can either have a will prepared or start making transfers of property. She really should do this as soon as possible since your stepfather is in ill health now.