First, it is right to be filial to our parents, because our parents raised us with hardships, and we should know how to be grateful.
Secondly, it is right to raise children, because since our parents are responsible for their children as soon as they are born, we should do our duty to raise and educate them, and it is our responsibility as parents to raise them.
As for whether my sister should be duty-bound to be kind to her sister, it depends on what is a good way. In childhood, because my sister is older than my sister, my sister can take care of her and love her in daily life. But you can't give her everything, it will make her form bad habits.