Sahih al-Bukhari 2620
Narrated Asma' bint Abu Bakr:
My mother came to me during the lifetime of Allah's Messenger (ﷺ) and she was a pagan. I said to Allah's 
Apostle (seeking his verdict), "My mother has come to me and she desires to receive a reward from 
me, shall I keep good relations with her?" The Prophet (ﷺ) said, "Yes, keep good relation with her. "
حَدَّثَنَا عُبَيْدُ بْنُ إِسْمَاعِيلَ، حَدَّثَنَا أَبُو أُسَامَةَ، عَنْ هِشَامٍ، عَنْ أَبِيهِ، عَنْ أَسْمَاءَ بِنْتِ أَبِي بَكْرٍ ـ رضى الله عنهما ـ قَالَتْ قَدِمَتْ عَلَىَّ أُمِّي وَهْىَ مُشْرِكَةٌ، فِي عَهْدِ رَسُولِ اللَّهِ صلى الله عليه وسلم، فَاسْتَفْتَيْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم قُلْتُ ‏{‏إِنَّ أُمِّي قَدِمَتْ‏}‏ وَهْىَ رَاغِبَةٌ، أَفَأَصِلُ أُمِّي قَالَ ‏
"‏ نَعَمْ صِلِي أُمَّكِ ‏"‏‏.‏