Praise be to Allah.
We praise Allaah for having guided you to become religiously committed and righteous, and to repent. We ask Him to forgive you for the wrongs that you have mentioned towards your sisters and their daughters. You have to pray for forgiveness a great deal and do many righteous deeds, and keep away from the things that lead to sin.
The door of repentance is open, no matter how great the sin, as Allaah says (interpretation of the meaning):
“Know they not that Allaah accepts repentance from His slaves and takes the Sadaqaat (alms, charity), and that Allaah Alone is the One Who forgives and accepts repentance, Most Merciful?”
“And verily, I am indeed forgiving to him who repents, believes (in My Oneness, and associates none in worship with Me) and does righteous good deeds, and then remains constant in doing them (till his death)”
Repentance erases that which came before it of sin, no matter how great or how many the sins. Allaah says:
“Say: O ‘Ibaadi (My slaves) who have transgressed against themselves (by committing evil deeds and sins)! Despair not of the Mercy of Allaah, verily, Allaah forgives all sins. Truly, He is Oft‑Forgiving, Most Merciful”
As for restoring rights, you have to make a lot of du’aa’ and pray for forgiveness for those whom you wronged, and Allaah accepts the repentance of the one who repents.
And Allaah knows best.