Lubaba bint al-Harith, Umm al-Fadl, wife of al-ʿAbbas, the Prophet’s uncle ﷺ, and sister of Maymuna, Mother of the Believers, is said to have been the first woman to embrace Islam after Khadija; she is the mother of Ibn ʿAbbas. On the day of ʿArafa, as people wondered whether the Prophet ﷺ was fasting, she sent him a bowl of milk, which he drank (al-Bukhari 1988).
Lubaba comes from lubab, “the core of a thing”: Ibn Manzur explains that the lubb and lubab of anything are its purest and best part, like the kernel inside the fruit. From the same root l-b-b comes lubb, “intelligence”, hence the ulu al-albab, “people of understanding”, whom the Quran so often addresses (3:190). The name thus expresses the essence, the best part. The Companion Abu Lubaba bears it in his kunya.
Is one who is devoutly obedient during periods of the night, prostrating and standing [in prayer], fearing the Hereafter and hoping for the mercy of his Lord, [like one who does not]? Say, "Are those who know equal to those who do not know?" Only they will remember [who are] people of understanding.
There was certainly in their stories a lesson for those of understanding. Never was it [i.e., the Qur’ān] a narration invented, but a confirmation of what was before it and a detailed explanation of all things and guidance and mercy for a people who believe.