Estate Law Questions? Ask an Estate Lawyer.
Thank you for your question. I look forward to working with you to provide you the information you are seeking for educational purposes only.
I am afraid that to change deeds on property some form of probate is necessary. Because it is more than 4 years since death, you may be able to use the simple process called muniment of title in Texas, you are going to have to file regular probate and ask for a muniment of title, because if a will is not filed after 5 years, the will can be declared null and void and the court now has to determine the heirs. So that is your alternative to getting his heirs to sign off I am afraid.
If the attorney knew about the house and did not bother telling you that the deed needed to be amended at that time, then he likely committed malpractice, but 10 years later is too late to even sue him for malpractice based on the short Texas statute of limitations to sue for that.