Hello Customer (name blocked for privacy),
If you don't appear, they have no right to do anything to you in Mississippi, but can hold you in contempt if you return to Texas some time. You were apparently properly served, but what can they do to you if you don't go? File a contempt of court, and wait to see if they ever catch you in Texas again. This is a civil action, and I doubt they will go this far.
Are you obligated to go? By Texas courts, yes.
It's up to you in the end.
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