It is narrated from Sayyidah Asma' bint Abi Bakr (may Allah be pleased with her) that when Abdullah bin al-Zubayr was born, he was brought to the Prophet (peace and blessings be upon him). He (peace and blessings be upon him) wiped over him, supplicated for him and named him Abdullah. Then, when he was seven or eight years old, he came at the instruction of Zubayr (may Allah be pleased with him) to give the pledge of allegiance to the Messenger of Allah (peace and blessings be upon him). When the Messenger of Allah (peace and blessings be upon him) saw him coming towards him, he smiled, and took his pledge.
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 20715