I am a 20 year old step-daughter, and my mom and step-dad want for him to adopt me. My mothers health is not good (she has Hep C and other liver problems) and in all reality, she probably does not have much time left.
Call it paranoia, but I would like to know the legal differences of this action. Especially when it concerns wills, inheritance, etc.

Thanks in advance!

Your step father can write you in his will to inherit whatever he wants you to inherit. He can make you executor of his estate, you can inherit property and/or monies, etc.

Does he have natural heirs, such as children from a previous marriage/relationship? Or other relatives that would surface after his death? If he did adopt you, you would have some legal protection as an heir, should he die without a will.

My advice would be for him to make out a will. Wills are not a document set in stone forever - they can be amended by him. But it is an important document for him to create, with an attorney. Does your Mother have a will?