You can go to the Harris County courthouse - where I assume that the "adoption" would have taken place. If there was an adoption it was probably "sealed" and the clerk will tell you there was a file -- but it was "sealed". That will let you know that an adoption probably occurred. If you cannot find anything, then perhaps no adoption occurred.
It's free to go to the Harris County Civil Courthouse in downtown Houston on 201 Caroline, Houston, TX 77002 on the second floor. They might charge a fee is you don't have a cause number - but it's not much. You need cash or a credit card - no personal checks accepted. They are open from approximately 8-4 pm Mon- Fri.
There are also computers available for free to the public towards the back of the room to use to access Harris County records. You might be able to do some research there on your own. Some people are helpful if you look lost - just ask.
If your parental rights were legally terminated then you have no parental rights any longer. You will have to wait until your child turns 18. Then he can do whatever he wants.
On a brighter note, your son obviously knows who you are and he is still able to have some sort of "contact" with you. If your parental rights were legally terminated, then your mother holds "all the cards". If you want access to this child, then you need to be nice to her.
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