Твои сёстры тоже не разрешает своим слугам улыбаться. DON'T your sisters let...? ¿

Tatiana, the original question is correct, and so is your translation.

Thank you! Is there any difference between these two?

Yes, with DO at the beginning, you’re just finding out if it’s a fact; with DON’T you’re surprised she doesn’t.

Cool! 🙏