Abraham's wife Sarah was sterile. She had been given an Egyptian woman, Hajar, as a servant. Abraham had aged, and his hair was gray after many years spent in calling people to Allah. Sarah thought that she and Abraham were lonely because she could not have a child. Therefore, she offered her husband her servant Hajar in marriage. Hajar gave birth to her first son Ishmael (Ismail) when Abraham was an old man.
Related Quran Ayaaths of this Hadith.
Surah 6 : Ayah 83 Surah 4 : Ayah 163 Surah 14 : Ayah 35 Surah 60 : Ayah 4 Surah 21 : Ayah 51 Surah 21 : Ayah 52 Surah 3 : Ayah 65"When a person dies, his works end, except for three: ongoing charity, knowledge that is benefited from, and a righteous child who prays for him."
Prophet Mohammed (PBUH)
"The best of what a man leaves behind are three: a righteous child who supplicates for him, ongoing charity the reward of which reaches him, and knowledge that is acted upon after him."
Sunan Ibn Mājah
"Every day two angels come down from Heaven and one of them says, 'O Allah! Compensate every person who spends in Your Cause,' and the other (angel) says, 'O Allah! Destroy every miser.'"
Sahih Bukhari