Is the elder sister obligated to educate her younger sister and her mother about the rulings of menstruation, ghusl, and purification from it, and what is the ruling on the multiple vaginal discharges that occur before menstruation, and do they necessitate ghusl?

Educating children in matters of their religion is a religious duty upon parents, based on the Almighty's saying: (O YOU WHO HAVE BELIEVED, PROTECT YOURSELVES AND YOUR FAMILIES FROM A FIRE), and the Prophet's (peace be upon him) saying: (ALL OF YOU ARE SHEPHERDS, AND ALL OF YOU ARE RESPONSIBLE FOR YOUR FLOCK). The family should also teach each other legal rulings if some members are ignorant of them, especially rulings related to puberty, even if it is from a younger to an older person. As for recurrent vaginal discharge, it does not necessitate ghusl (definition) (ritual bath); ghusl is only necessitated by janabah (definition) (state of ritual impurity) and menstruation.