The Prophet said: "Whichever man married a woman and entered into her, then it is not lawful for him to marry her daughter. If he did not enter into her then he may marry her daughter. And whichever man married a woman and he entered into her, or he did not enter into her, then it is not lawful for him to marry her mother."  

أَنَّ النَّبِيَّ ﷺ قَالَ أَيُّمَا رَجُلٍ نَكَحَ امْرَأَةً فَدَخَلَ بِهَا فَلاَ يَحِلُّ لَهُ نِكَاحُ ابْنَتِهَا فَإِنْ لَمْ يَكُنْ دَخَلَ بِهَا فَلْيَنْكِحِ ابْنَتَهَا وَأَيُّمَا رَجُلٍ نَكَحَ امْرَأَةً فَدَخَلَ بِهَا أَوْ لَمْ يَدْخُلْ بِهَا فَلاَ يَحِلُّ لَهُ نِكَاحُ أُمِّهَا