Dear parents in the Thai restaurant,
The place filled up quickly. The only seats we could get were next to your table. You decided the best way to parent was to talk to each other and let your child play some loud video on a tablet. Our dirty looks didn't seem to get the message across that this clearly disturbed most of the other people in the place. Nor did asking the server to talk to you (Which she said she would do, then didn't), nor did asking you directly. What excuse are we using today? Parenting is hard work, we all need a break? Children are our future? We all have a right to be obnoxious in public spaces? None of those work.
You have options— Actually parent your child and teach them that engaging with those around them is the key to a healthy social life, and that their parents actually give a shit about them. Or don't bring them at all. Either one is preferable to us having to hear that noise, and having to watch you bring up another generation that is more at home with the internet than with real life.
P.S. Dear server in the same restaurant,
If you're too chickenshit to confront diners about behavior that affects other patrons, learn to get good at being tipped less and having disgruntled people not return. The food was great, the atmosphere, eh, not so much. At the very least, don't lie and say you're going to do something about it.