It depends how you "changed ownership". If you executed a deed, changing title to a Life Estate, then it would depend if you created an Enhanced Life Estate (Revocable Life Estate). If you didn't change the title on a deed and you are leaving them the house in a will, then you can create and execute a codicil. You should consult with an attorney to evaluate the title and any other documents you have regarding the house, in order to fully answer your question.
It depends how you "changed ownership". If you executed a deed, changing title to a Life Estate, then it would depend if you created an Enhanced Life Estate (Revocable Life Estate). If you didn't change the title on a deed and you are leaving them the house in a will, then you can create and execute a codicil. You should consult with an attorney to evaluate the title and any other documents you have regarding the house, in order to fully answer your question.