(14) باب فَضْلِ النَّفَقَةِ وَالصَّدَقَةِ عَلَى الْأَقْرَبِينَ وَالزَّوْجِ وَالْأَوْلَادِ وَالْوَالِدَيْنِ وَلَوْ كَانُوا مُشْرِكِينَ
Asma' daughter of Abu Bakr reported:
I said: Messenger of Allah, my mother, who is inclined or scared has come to me. Should I (even An her position of being opposed to Islam) treat her well? He said: Yes.
Reference: Sahih Muslim 1003 a
In-book reference: Book 12, Hadith 61
USC-MSA web (English) reference(deprecated numbering scheme): Book 5, Hadith 2194