Don’t worry, her kids can’t be there since her ex won’t consent to videotaping. And also it’s his weekend. Yet she thinks it’s a “family” show thing. Karma is a bitch.
I would wait until everyone is seated at the table, then smash clean through the front door on my motorcycle, shatter the fireplace mirror with my helmet and scream at mom “Whats for supper, ya ol’ scullery maid?!?!?!” ...Then I would ride off into the sunset, and let the road take me to wherever destiny needs me.
I don't think subtlety should be part of the plan at all. Give them the antics and drama that the masses want, then refuse to be part of the show if it gets picked up. That will show her who the star is, she'll be begging for your help, she will be denied. You don't want to be seen on television? You should go to dinner in disguise. Paint your face like a member of KISS. Make and wear a shirt that says "I'm with an idiot that thinks she's interesting" with an arrow, sit next to your sister. It's been said before, but fire and/or explosions will be your friend... and you'll be using it for good so, you know, maybe it will not turn on you this time. Bring an offering of roadkill and a bucket of stump water for your gracious dinner host. Break out the Ass-less chaps for this dinner, you're from Texas, we know chaps are nearby. Are there cacti in your part of Texas? I think you should slip one in your sisters chair just before she sits. Use chopsticks to eat, claim to be %4 North Korean, as determined by one of those DNA test you see on television. I'd like to high five your ex-brother in-law for not allowing the kids to be part of this nonsense.
This is turning out perfectly and blowing up before I can even stir the pot. Various family members are now refusing to be involved (see her aforesaid being a bitch and essentially away from the family for the past decade only showing up when she needs something). Those who are going, are going to be arriving VERY intoxicated with plans to drink throughout. It only lasts an hour and a half. She has told her boyfriend, who we all know will propose in the next year, not to attend because the show is supposed to be about her being a single mother. I’m now really looking forward to this shitshow.