My mother came to me during the time of the treaty with Quraysh, and she was a polytheist. I asked the Messenger of Allah ﷺ, "Should I maintain ties with her?"He replied, "Yes."
حدثنا سفيان
أتتني أمي راغبة في عهد قريش وهي مشركة فسألت رسول الله ﷺ أصلها قال نعم
Its chain of transmission is sahih. Bukhari narrated it, 5/233, no. 2620, in the book of gifts, and Muslim, 2/696, no. 1003, and Abu Dawud, 2/127, no. 1668, both in the book of zakat.