Is written online correspondence for the purpose of marriage permissible, with the sister's knowledge and assurance that Islamic regulations are not overstepped, or not? And does a man's agreement to marry a girl who carries a genetic disease that might affect the children constitute a crime against them? And must a girl adhere to her mother's oath not to marry outside her city, especially with her delayed marriage and illness?

Online interaction between young men and women for the purpose of marriage is fraught with risks and has been forbidden. The necessary information about a girl can be obtained through trustworthy relatives. If the communication was limited to what was mentioned and no forbidden acts were committed, there is no sin for what has passed, but the relationship must be severed to prevent the temptation of Satan.

As for marrying a girl with a hereditary disease, there is no objection to it. Procreation can be avoided by 'azl (coitus interruptus), or by relying on Allah, because procreation and the occurrence of diseases are matters of the unseen, and a believer may be rewarded for the afflictions that befall him. Obedience to parents takes precedence over marrying a specific person.