"When the Prophet (ﷺ) arrived at Medina, the eldest amongst his companions was Abu Bakr. He dyed his hair with Hinna and Katam till it became of dark red color.
Sahih al-Bukhari Book 63, Hadith 145
← Previous Hadith (the servant of the Prophet) When the Prophet (ﷺ) arrived (at Medina), there was not a single companion of the Prophet (ﷺ) who had grey and black hair except Abu Bakr, and he dyed his hair with Henna' and Katam (i.e. plants used for dying hair).

Sahih al-Bukhari Book 63, Hadith 144 Next Hadith → Abu Bakr married a woman from the tribe of Bani Kalb, called Um Bakr. When Abu Bakr migrated to Medina, he divorced her and she was married by her cousin, the poet who said the following poem lamenting the infidels of Quraish: "What is there kept in the well, The well of Badr, (The owners of) the trays of Roasted camel humps? What is there kept in the well, The well of Badr, (The owners of) lady singers And friends of the honorable companions; who used to drink (wine) together, Um Bakr greets us With the greeting of peace, But can I find peace After my people have gone? The Apostle tells us that We shall live again, But what sort of life will owls and skulls live?:

Sahih al-Bukhari Book 63, Hadith 146