“I have two two-year-old daughters. I compare them with my peers and I am careful, these develop very well mentally. The trouble is there, that one of them has been reporting physiological needs for several months, and the other does not. Please explain the reasons and advice, how to get your second child to do the same.”
To accurately explain the causes of the problem that worries you, I would need more data on the development of the troubled little daughter. However, even the meager information on this subject allows me to make some assumptions. Maybe a little girl, what time do you write about, was born second. So her delivery lasted longer and may have caused brain hypoxia. Please don't be scared. This fact does not have to be the cause of serious development disorders, but may cause some slight delay, The easier it is for you to observe it, because you can constantly compare your little daughters.
My advice is to be very patient, understanding, tolerant of the "younger" daughter. You have doubts, make no mistakes, spending a lot of time explaining to your child what you expect from him / her. I think, that persuasion reaches a small child to a very limited extent.
I propose, to put your child on the potty, not only in the situations described by you, but also after sleeping, when the diaper has been dry for some time, about half an hour after drinking. It's also a good idea to do it at regular intervals. Please don't burden yourself with any guilt and don't think, that only possible educational mistakes made by you can cause difficulties, what you encounter.
A child is born with a set of features and predispositions. There are children, which can be easily controlled and quickly approach the ideal dreamed by their parents, there are also such, with which work requires more effort.