In Texas, the duration of such possession is three (3) to twenty-five (25) years, depending upon the circumstances of the case. Texas Civ. Prac. Rem. Code §16.021 through 16.032.
from this site:
http://www.lawchek.net/resources/forms/que/advposs.htm
I haven't been to Texas' website yet but apparently there are several variables possible. To assist those willing to assist you, maybe you could post any possibly pertinent info.