IMHO given the fact that your 2-year-old child was next to you, no jury in Texas would convict you of any wrongdoing. I would not have done anything different.
OTOH if I were alone in the same situation, I would have first backed up rapidly while loudly exclaiming "I HAVE A GUN- BACK OFF!!" If they did not respond by the count of 2, then
I would draw.