Abu Hurayrah (may Allah be pleased with him) was single, without wife or child when he became a Muslim. With him however was his mother who was still a mushrik (idolator). He longed, and prayed, for her to become a Muslim but she adamantly refused. One day, he invited her to have faith in God alone and follow His Prophet but she uttered some words about the Prophet which saddened him greatly. With tears in his eyes, he went to the noble Prophet who said to him: "What makes you cry, O Abu Hurayrah?" "I have not let up in inviting my mother to Islam but she has always rebuffed me. Today, I invited her again and I heard words from her which I do not like. Do make supplication to God Almighty to make the heart of Abu Hurayrah's mother incline to Islam." The Prophet responded to Abu Hurayrah's request and prayed for his mother. Abu Hurayrah said: "I went home and found the door closed. I heard the splashing of water and when I tried to enter my mother said: "Stay where you are, O Abu Hurayrah." And after putting on her clothes, she said, "Enter!" I entered and she said: "I testify that there is no god but Allah and I testify that Muhammad is His Servant and His Messenger." "I returned to the Prophet, peace be on him, weeping with joy just as an hour before I had gone weeping from sadness and said: "I have good news, O Messenger of Allah. God has responded to your prayer and guided the mother of Abu Hurayrah to Islam." Source: "Biographies of Companions" extracted from the Al-Alim software.
Let us make strong effort and supplications so that our parents can be guided if they are not already.