Abu Hurairah reported,

The Prophet ﷺ visited his mother's grave and wept, and those around him wept as well. Then he said, "I asked my Lord's permission to visit my mother's grave, and He granted me permission. I asked Him for permission to seek forgiveness for her, but He did not grant me that. So visit the graves, for they will remind you of death."

Azami 8522

Sahih

عن أبي هريرة قال

زار النبي ﷺ قبر أمه فبكى، وأبكى من حوله ثم قال: استأذنت ربي في زيارة قبر أمي فأذن لي، واستأذنته الاستغفار لها فلم يأذن لي، فزوروا القبور تذكركم الموت.

الأعظمي 8522صحيح
Contents
Reference
Commentary
Ayat
Collection
Jami al-Kamil
Book
Biography of the Prophet ﷺ
Section
Parents of the Prophet ﷺ
Numbering
Jami al-Kamil 8522 (2nd edition)