It is narrated from Sayyidah Asma bint Abi Bakr (may Allah be pleased with her) that she said: I said: O Messenger of Allah! My mother has come to me, hoping and fearful; shall I maintain ties with her? He (peace and blessings be upon him) said: "Maintain ties with her."
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 20576