There is a new Texas law effective September, 2017 that anyone under the age of 18 cannot marry.
The only exception is a judge can emancipate the teen-ager (between the ages of 16-18) and then the newly emancipated person can marry.
No longer can parents just sign and agree to the marriage - that is now GONE.
If you are unhappy, contact your Texas legislature since they changed the law effective September 2017.
If enough people complain, then the legislature can re-visit this law when they meet again in 2019.
Emancipation is not cheap or easy. It will definitely depend on the judge. Some judges won't do it. Of course, what makes it truly difficult is that the teen-ager needs to be financially self reliant. I don't know of any 16 year olds that support themselves 100%.
But the law is new so perhaps judges will be more lenient if they know that the child intends to marry as soon as they are emancipated.
Lots of parents and teens post regarding this question and I hope this explains it clearly and simply.
It's the current law and we are struck with it until the legislature changes the law.