1) First, check to see what date this is from, exactly. If this is over 4 years, then statute of limitations prohibits them from suing, assuming that the debt was from Texas. The date is the last of (a) the time that the account became delinquent, (b) the time that a payment was made, or, (c) the time that the individual affirmed the debt in writing.
2) If sued, you want to file an ANSWER to avoid default. This will kick the matter into trial mode which would be months down the line. If so, then this gives time to the parties to negotiate. You may find that the other party will agree to a lesser amount. If they do not, then the best leverage here to use is to threaten bankruptcy (they do not know that you may be bluffing). A BK during or after judgment will reduce the debt to pennies on the dollar, or eliminate it all together. So one can say I will pay you $x amount, and no more, or I will file bankruptcy to avoid judgment and you will not see a penny. They often will agree with you to accept something lesser than the amount they seek.
Let me know if you need a sample Answer to file.
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