Ulayya bint al-Mahdi in the context of "Ibrahim ibn al-Mahdi"

Ibrāhīm ibn al-Mahdī (Arabic: إبراهيم بن المهدي; 779–839) was an Abbasid prince, singer, composer and poet. He was the son of the third Abbasid caliph, al-Mahdi, and the half-brother of the poet and musician Ulayya. Ibrahim was contemporary of Abbasid caliph al-Hadi, al-Rashid and his three nephews caliph al-Amin, al-Ma'mun, al-Mu'tasim.